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Won't Idle below 1000

Printed From: CorrectCraftFan.com
Category: Repairs and Maintenance
Forum Name: Engine Repair
Forum Discription: Engine problems and solutions
URL: http://www.CorrectCraftFan.com/forum/forum_posts.asp?TID=17148
Printed Date: June-23-2024 at 3:10pm


Topic: Won't Idle below 1000
Posted By: WhiteLakeSkier
Subject: Won't Idle below 1000
Date Posted: April-15-2010 at 7:47pm
!984 302 ford. I have a feeling the timing is off. it says 6 degrees advance at 600 rpm, however I can not get it to idle that low to adjust. I can only sort of guess. Any numbers on how many degrees at higher rpms? Or is this a carb issue? It also idles in a way that makes it rev up and then back down again in the range of a few hundred rpms. Any Ideas?

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www.correctcraftfan.com/diaries/details.asp?ID=5120&sort=&pagenum=1 - 1961 CC Custom American Skier



Replies:
Posted By: storm34
Date Posted: April-15-2010 at 7:48pm
Your last statement makes me think it'd be a carb issue. But I'm no mechanic either!

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Posted By: TRBenj
Date Posted: April-15-2010 at 7:53pm
Set the timing to 10 deg BTDC at idle (below 1000 rpm). Then go after your carb to adjust the idle correctly. Set the mixture screws for max vaccuum, then adjust the curb to ~700. Setting the idle works better under load (ie, in gear- in which case, set it to 650). Double check your timing after youre done. You should see 10 at idle and ~34-36 by 3000 RPM.

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Posted By: WhiteLakeSkier
Date Posted: April-15-2010 at 8:05pm
well I can barely get it under 1000. So should I set it to 10 at 1000? Where are the mixture screws and how do I know they are set to max vacuum? Turn left for max vacuum?

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www.correctcraftfan.com/diaries/details.asp?ID=5120&sort=&pagenum=1 - 1961 CC Custom American Skier


Posted By: TRBenj
Date Posted: April-15-2010 at 8:17pm
The idle mixture screws are located in the front metering plate- there is one on either side of the carb. Set them to 1.5 turns out before you start, and adjust from there. You will need a vacuum gauge hooked up to the intake (borrow the PCV port) to accurately judge max vacuum. Else, you can ballpark where the idle is the highest. Both screws should be set the same. Turn them in 1/4 turn increments.

Set the timing at 10 deg to start (just so it idles), then adjust your carb. After youre done, you will want to recheck your timing- and possibly go through the carb one more time.

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Posted By: WhiteLakeSkier
Date Posted: April-15-2010 at 8:49pm
1000 degrees? Do you mean 10?

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www.correctcraftfan.com/diaries/details.asp?ID=5120&sort=&pagenum=1 - 1961 CC Custom American Skier


Posted By: TRBenj
Date Posted: April-15-2010 at 8:51pm
Yes, 10 deg

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Posted By: WhiteLakeSkier
Date Posted: April-15-2010 at 8:54pm
How come I read 6 degrees BDC on the valve cover, yet I should set it to 10? Which one?

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www.correctcraftfan.com/diaries/details.asp?ID=5120&sort=&pagenum=1 - 1961 CC Custom American Skier


Posted By: TRBenj
Date Posted: April-15-2010 at 8:59pm
Set it to 10.

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Posted By: 81nautique
Date Posted: April-15-2010 at 9:00pm
Originally posted by WhiteLakeSkier WhiteLakeSkier wrote:

It also idles in a way that makes it rev up and then back down again in the range of a few hundred rpms. Any Ideas?


Have you checked for vacuum leaks?


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You can’t change the wind but you can adjust your sails


Posted By: TRBenj
Date Posted: April-15-2010 at 9:04pm
I thought of the same thing also, Alan. I figured it would be best to try to set the idle properly since he's already messed with it. But it begs the question- has the motor been apart (carb, intake, etc)? Any chance the PCV port on the carb spacer isnt connected?

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Posted By: WhiteLakeSkier
Date Posted: April-15-2010 at 9:26pm
The engine was apart. Intake manifold, carb, spacer. Would the idle that wanders up and down be caused by a vacuum leak? I can't set the idle much since it will not stay steady. I turned both screws in all the way and then adjusted 1/4 turn out until the low part of the wandering was at 650/700. However, it won't stay like this for more than a minute or so, the wandering will eventually bring it too low and it stalls.

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www.correctcraftfan.com/diaries/details.asp?ID=5120&sort=&pagenum=1 - 1961 CC Custom American Skier


Posted By: Luchog
Date Posted: April-15-2010 at 9:54pm
start the engine and spray some w40 on the intake perimeter, bolts, and carb/spacer base, look for bubbles.

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http://www.correctcraftfan.com/diaries/details.asp?ID=2095" rel="nofollow - 1980 Ski Nautique

Commander 351W


Posted By: Hollywood
Date Posted: April-15-2010 at 9:57pm
I am shocked you are having problems.

Originally posted by WhiteLakeSkier WhiteLakeSkier wrote:

I may not have the degree, but I can easily do what the mechanic does.


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Posted By: WhiteLakeSkier
Date Posted: April-15-2010 at 10:06pm
I lost it all over the winter!

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www.correctcraftfan.com/diaries/details.asp?ID=5120&sort=&pagenum=1 - 1961 CC Custom American Skier


Posted By: WhiteLakeSkier
Date Posted: April-16-2010 at 12:51pm
I found that the erratic idle is because of a leak in the manifold, maybe even carburetor. I sprayed some starter fluid around the seals of the manifold and the engine would pick right up. Accurate? I also noticed when I took the manifold and carb off that there was two gaskets on top of the spacer, might be the source of some of my troubles eh?

When I put it back together, I know the hose from the spacer goes rear, however is it designed so that one side goes to the carb, one goes to the manifold? What do the correct gaskets look like for the manifold/spacer seam and the spacer/carb seam. I want to make sure it is all correct so I'm not doing this again.

Now the intake manifold gaskets, any specifc kind? I got them from pep boys last time for a 1984 ford 302 mustang car. All the ports matched up on the gasket and head. Do I use any sealant with the gasket? I used it last time just to hold it in place, and I applied a little more with the cork end pieces.


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www.correctcraftfan.com/diaries/details.asp?ID=5120&sort=&pagenum=1 - 1961 CC Custom American Skier


Posted By: 79nautique
Date Posted: April-16-2010 at 1:41pm
Well don't use the cork piece on each end use permatex RTV and also use it around all four water ports before you install the intake.

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http://www.correctcraftfan.com/diaries/details.asp?ID=756&sort=&pagenum=1&yrstart=1979&yrend=1979 - 79 nautique


Posted By: davidg
Date Posted: April-17-2010 at 1:16am
Other than carb, or vacuum leak issues, you may also have a worn timing chain. I put a new timing chain on when I rebuilt my engine, and it made a big difference....as well as following all the advice above. Before I did all those things, my engine (351) would also not idle below 1000 rpm.   


Posted By: eric lavine
Date Posted: April-17-2010 at 11:26am
if the timing chains are worn, you typically will see this in the timing mark...it will have a tendency to be erratic and not steady when checking with a light.
first thoughts though were vacuum also

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"the things you own will start to own you"


Posted By: WhiteLakeSkier
Date Posted: April-19-2010 at 1:06pm
I took the manifold/carb off and replaced the gaskets again. All works great now. The idle is smooth and does not jump. However, I have the idle adjustment screw backed all the way out and It will only idle at 650/700. Shouldn't I be able to back it all the way out until it stalls? I have no wiggle room now, should it ever go higher, I can't adjust it lower. The gaskets are not leaking, as I have sprayed starting fluid around them all and no engine response from it. I took the PCV valve hose out of the cover and held my finger over it, didn't go any lower. Adjusting lean or rich has not helped either. Could it be the timing? The mark is not erratic at all. I had it set to 10 degrees advance, however the idle was even higher than. So I put it back to valve cover spec of 6 degrees and 650/700 is where I am at now. It just seems like I should be able to adjust it low enough to stall.

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www.correctcraftfan.com/diaries/details.asp?ID=5120&sort=&pagenum=1 - 1961 CC Custom American Skier


Posted By: Luchog
Date Posted: April-19-2010 at 1:19pm
Put the timing lamp in again and set advance to 8-10 degrees. (8 being shy, 10 if you're sure you have a really healthy engine)

Do this with the iddle mixture screws 1.5 turn open.

lower the accelerator pump iddle screw as it might be set too high and your carb's running on the transition slots. It is located below the accelerator cable attaching mechanism on the carb.

once you get to the 750rpms mark again, start tuning the iddle mixture screws again. If you close them all the way and engine does not stumble, you iddle passages could be clogged.

Remember you want 600-650rpms at iddle in gear, at neutral you will need more like 750-800rpms.



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http://www.correctcraftfan.com/diaries/details.asp?ID=2095" rel="nofollow - 1980 Ski Nautique

Commander 351W


Posted By: WhiteLakeSkier
Date Posted: April-19-2010 at 2:04pm
Alright, so is the accelerator pump idle screw separate from the screw that adjusts the throttle on the carb?

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www.correctcraftfan.com/diaries/details.asp?ID=5120&sort=&pagenum=1 - 1961 CC Custom American Skier


Posted By: TRBenj
Date Posted: April-19-2010 at 2:15pm
A few things:

-There are 2 idle mixture screws. Did you adjust both of them or just one? They should be set the same.

-The idle mixture screws should be adjusted for max vaccuum (which will usually correspond with max RPM at idle), NOT for optimum RPM. The curb idle adjustment is used to set your RPM properly afterwards.

-Set the timing FIRST, before dinking with the idle. The boat will generally run better at 10 than 6.

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Posted By: 79nautique
Date Posted: April-19-2010 at 2:16pm
Originally posted by Luchog Luchog wrote:



once you get to the 750rpms mark again, start tuning the iddle mixture screws again. If you close them all the way and engine does not stumble, you iddle passages could be clogged.





If it doesn't stall then your not on the idle circut to start with and need to disconnect the throttle cable at the carb and adjust the carb and timing then adjust the throttle cable properly.


if you have been making these adjustments with the throttle cable attached to the carb disconnect it and see if the rpms drop I bet they do since the screw is all of the way out and the engine isn't dieing then the carb's throttle plate is being held open by the throttle cables adjustment.

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http://www.correctcraftfan.com/diaries/details.asp?ID=756&sort=&pagenum=1&yrstart=1979&yrend=1979 - 79 nautique


Posted By: vondy
Date Posted: April-19-2010 at 5:37pm
Don't forget to adjust your idle speed screw as well.

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http://correctcraftfan.com/diaries/details.asp?ID=4645&sort=&pagenum=1 - 69 Mustang HM


Posted By: WhiteLakeSkier
Date Posted: April-19-2010 at 6:07pm
The cable has not been attached at all, and I check the timing as I'm adjusting things. When I adjust the mixture screws equally the engine runs at the same rpm. Regardless of where they are set lean/rich.

I actually have the idle speed screw completely taken out, so that is not affecting the lever at all. I notice that the lever is not touching where the idle adjustment screw screws into. It is almost as if the carb has bottomed out internally.

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www.correctcraftfan.com/diaries/details.asp?ID=5120&sort=&pagenum=1 - 1961 CC Custom American Skier


Posted By: vondy
Date Posted: April-19-2010 at 7:11pm
Did you ever get a vacuum gauge to adjust your idle mixture? I got one at Northern Tool last year for 15 - 20 bucks. It really helps when adjusting idle mixture.

Also is your engine reverse rotation? Are your timing marks going the right direction? The marks on my reverse rotation 302 are for a left hand engine. So 10 degrees ATDC on the mark is actually 10 degrees BTDC.

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http://correctcraftfan.com/diaries/details.asp?ID=4645&sort=&pagenum=1 - 69 Mustang HM


Posted By: WhiteLakeSkier
Date Posted: April-19-2010 at 8:57pm
Hmmm, How can I tell if it is reverse rotation? The motor spins counterclockwise when looking at the flywheel. I still need to get a vacuum gauge, do I just hook into the PCV line? It just troubles me that I cannot adjust the idle to stall. Something is not right and I don't know what else to adjust!

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www.correctcraftfan.com/diaries/details.asp?ID=5120&sort=&pagenum=1 - 1961 CC Custom American Skier


Posted By: TRBenj
Date Posted: April-19-2010 at 9:11pm
Have you adjusted your curb, as mentioned (several times) above?

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Posted By: WhiteLakeSkier
Date Posted: April-19-2010 at 9:16pm
Yes, set at 10 degrees

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www.correctcraftfan.com/diaries/details.asp?ID=5120&sort=&pagenum=1 - 1961 CC Custom American Skier


Posted By: TRBenj
Date Posted: April-19-2010 at 9:21pm
Clearly we have a communication issue! I'm not asking about the timing, Im asking if you adjusted the curb idle adjustment screw (presumably a Holley on that PCM):



If there is a piece of advice that confuses you, ask!

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Posted By: vondy
Date Posted: April-19-2010 at 9:22pm
If you sitting in the back of the boat looking forward is your engine turning clockwise or counterclockwise?

Clockwise would be right hand, reverse, rotation. Counterclockwise would left hand rotation.

If you look at your timing marks, from the front of the engine, is the BTDC side on the right of 0, TDC, or left?

My BTDC is on the right of TDC. And I have a reverse rotation engine so that means my timing marks are backwards. When this is the case you buy some timing tape, like I just did, and put it on upside down.

I went to ACE hardware and got some fittings to plug my vacuum gauge in on the manifold right behind the carb.

I removed the brass plug you see in this pic.


Here it is in my new manifold. The brass fitting to the right with the red cap. Sorry it's the only pic of it I have here at work.


You should be able to plug it into your PVC port on your spacer as well.

I'm no expert here so if anyone sees anything wrong please correct me.

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http://correctcraftfan.com/diaries/details.asp?ID=4645&sort=&pagenum=1 - 69 Mustang HM


Posted By: WhiteLakeSkier
Date Posted: April-19-2010 at 9:23pm
Ohhh I see! Sorry about that. Yes I have adjusted that. In fact it is sitting on my dash now! Still idles at 650/700!

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www.correctcraftfan.com/diaries/details.asp?ID=5120&sort=&pagenum=1 - 1961 CC Custom American Skier


Posted By: TRBenj
Date Posted: April-19-2010 at 9:26pm
Originally posted by vondy vondy wrote:

My BTDC is on the right of TDC. And I have a reverse rotation engine so that means my timing marks are backwards.

Vondy, Ive only seen/heard about the backwards timing marks on a handful of engines, and all were of the 60's to early 70's vintage. The marinizers must have gotten their act together soon after that, as every RR engine Ive dealt with (78 and newer) has had the marks going in the right direction. I suspect his mid-80's PCM to fall into that category.

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Posted By: vondy
Date Posted: April-19-2010 at 9:29pm
I'm sure it is. Just trying to think of anything.

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http://correctcraftfan.com/diaries/details.asp?ID=4645&sort=&pagenum=1 - 69 Mustang HM


Posted By: WhiteLakeSkier
Date Posted: April-19-2010 at 9:29pm
Well It must be RH then. I shall readjust timing then

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www.correctcraftfan.com/diaries/details.asp?ID=5120&sort=&pagenum=1 - 1961 CC Custom American Skier


Posted By: WhiteLakeSkier
Date Posted: April-19-2010 at 9:32pm
It runs well where it is. I doubt it would run this well if it was 20 degrees below where it should be?

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www.correctcraftfan.com/diaries/details.asp?ID=5120&sort=&pagenum=1 - 1961 CC Custom American Skier


Posted By: TRBenj
Date Posted: April-19-2010 at 9:37pm
If you were at 10ATDC, it might start ok, but wouldnt like any sort of load. Probably not your problem though, as you could still dial in your idle with wacked out timing.

If the curb adjustment has no effect, then something may be hung up- are the butterflies all closed?

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Posted By: 81nautique
Date Posted: April-19-2010 at 9:42pm
I think 79 has tried to communicate this to you but give this a try.

Back your curb idle all the way out which I think you have already done. Now turn your idle mixture screws in(closed) all the way(both sides). If the motor does not stall then you're not running on the idle circuit so we have to figure out why.

Is there any possible way your linkage is binding preventing the throttle from completely closing? Is there gasket material binding on the butterflies? Something is keeping the throttle part open.

Guys is there any way for the secondaries to be partly opening or how about a float level too high on the secondaries dumping fuel down? What about the secondary linkage, any possibilty of binding or bent linkage.

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You can’t change the wind but you can adjust your sails


Posted By: 79nautique
Date Posted: April-20-2010 at 12:28pm
Originally posted by WhiteLakeSkier WhiteLakeSkier wrote:

Ohhh I see! Sorry about that. Yes I have adjusted that. In fact it is sitting on my dash now! Still idles at 650/700!


ok maybe some games are being played.

But what's on the dash?

and Why is it now idling below 1000 and set about where it needs to be, I'm confused and about finished with any future help.

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http://www.correctcraftfan.com/diaries/details.asp?ID=756&sort=&pagenum=1&yrstart=1979&yrend=1979 - 79 nautique


Posted By: WhiteLakeSkier
Date Posted: April-21-2010 at 3:46am
The curb adjustment. I call it a screw that adjusts the lever to change idle. it is unscrewed and sitting on my dash. With that out, it will run at 650/700. Sure that is where I want to be, but shouldn't an engine stall with the screw taken all the way out?

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www.correctcraftfan.com/diaries/details.asp?ID=5120&sort=&pagenum=1 - 1961 CC Custom American Skier


Posted By: 91nautique
Date Posted: April-21-2010 at 5:10am
Originally posted by WhiteLakeSkier WhiteLakeSkier wrote:

I also noticed when I took the manifold and carb off that there was two gaskets on top of the spacer, might be the source of some of my troubles eh?

do the correct gaskets look like for the manifold/spacer seam and the spacer/carb seam. I want to make sure it is all correct so I'm not doing this again.


Guy's
Is there an exhaust crossover port on this model engine under the carb spacer?

If so what gasket did you use between the spacer and the manifold? (You can't use the standard gasket that you use between the carb and manifold)

It will burn through and leak exhaust gases into the engine under the spacer.


Posted By: 79nautique
Date Posted: April-21-2010 at 1:26pm
Originally posted by 91nautique 91nautique wrote:

Originally posted by WhiteLakeSkier WhiteLakeSkier wrote:

I also noticed when I took the manifold and carb off that there was two gaskets on top of the spacer, might be the source of some of my troubles eh?

do the correct gaskets look like for the manifold/spacer seam and the spacer/carb seam. I want to make sure it is all correct so I'm not doing this again.


Guy's
Is there an exhaust crossover port on this model engine under the carb spacer?

If so what gasket did you use between the spacer and the manifold? (You can't use the standard gasket that you use between the carb and manifold)

It will burn through and leak exhaust gases into the engine under the spacer.


this is not a car with an old fashoined choke coil mounted on the intake it has an electric choke so there is no exhaust port to worry about the gasket on top of the spacer is the same as the gasket on the botom of the spacer.

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http://www.correctcraftfan.com/diaries/details.asp?ID=756&sort=&pagenum=1&yrstart=1979&yrend=1979 - 79 nautique


Posted By: 82wake2001
Date Posted: April-21-2010 at 1:33pm
I had this exact issue with my 82...351...last weekend i changed the cap rotor all the plugs(autolite 24 gapped at .35) and 7mm plug wires from skidim...

side note the sales associates at skidim are amazing!!!!!

fired up the boat, by the way on the first crank without and throttle and adjusted the carb after it came up to temp.....

now i have it idling at 650 and can start the boat without using the throttle...

and the pipes sound mean when she is all tuned up....


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Joe
1982 ski nautique 2001
"Lady of the Wake"


Posted By: 91nautique
Date Posted: April-21-2010 at 10:07pm
Originally posted by 79nautique 79nautique wrote:

there is no exhaust port to worry about the gasket on top of the spacer is the same as the gasket on the botom of the spacer.


No there not, they are way different on the '91 and '95 351 Pcm's I have, and you can not use a standard base gasket between the spacer and manifold.

Mine has leaked through the port that supplies exhaust gas to the base plate to warm up the carb, and the engine behaved exactly like White lake skier's.

Skidim used to sell the correct gasket, but it is now unavailable.

Iv'e not seen a manifold on a '84 302 PCM like WL skier's, that's why I asked if they have the same setup as mine, and considering he has just pulled the manifold and baseplate off, this may well be the issue.

WL skier,
How was the motor running prior to pulling it apart?


Posted By: Luchog
Date Posted: April-21-2010 at 10:10pm
91nautique, why dont you post a pic of your "port that supplies exhaust gas to the base plate to warm up the carb"

I dont think anyone has one of those in their boats.

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http://www.correctcraftfan.com/diaries/details.asp?ID=2095" rel="nofollow - 1980 Ski Nautique

Commander 351W


Posted By: 91nautique
Date Posted: April-21-2010 at 10:38pm
Luchog,

Iv'e since changed the manifolds to Elderbrock performer's and thrown out the old manifolds.

The original gasket on both engine's looked like this one off a 351Clevland. It was very thick material and had a steel plate embedded into the gasket that covered the port.

Skidim used to sell them, and when I emailed them about it years ago they knew exactly what I was enquiring about.


Posted By: Luchog
Date Posted: April-21-2010 at 10:43pm
I think what you are refering to is the PCV port, wich connects the carb wedge plate to the valve cover.

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http://www.correctcraftfan.com/diaries/details.asp?ID=2095" rel="nofollow - 1980 Ski Nautique

Commander 351W


Posted By: lewy2001
Date Posted: April-21-2010 at 10:48pm
That is different 91. Were they Protec ignition engines? They may have some differences in the intake manifold as well. Very unusual

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If you're going through hell, keep going

http://www.correctcraftfan.com/diaries/details.asp?ID=2999" rel="nofollow - 89 Ski

<a href="http://www.correctcraftfan.com/diaries/details.asp?ID=5685" ta


Posted By: WhiteLakeSkier
Date Posted: April-22-2010 at 12:23am
It used to run perfect, until I took it apart! I am thinking it must be the gaskets. The old gaskets were identical top and bottom. The front barrels of the carb were open to eachother, and the rear was two individual barrels. The gaskets now on there are different. Bottom is like original, however the top has the front barrels open to eachother, as well as the rear open to eachother.

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www.correctcraftfan.com/diaries/details.asp?ID=5120&sort=&pagenum=1 - 1961 CC Custom American Skier


Posted By: 79nautique
Date Posted: April-22-2010 at 12:48pm
swap the gaskets locations only if the plate has four holes in it and isn't one large open area, if the plate is one large open area get two matching gaskets that are open like the plate is.

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http://www.correctcraftfan.com/diaries/details.asp?ID=756&sort=&pagenum=1&yrstart=1979&yrend=1979 - 79 nautique


Posted By: 91nautique
Date Posted: April-23-2010 at 12:06am
Luchog Said..I think what you are refering to is the PCV port.

No -way, the manifold had an exhaust port under the plate, thick gasket with shim over the port,and appeared to have never been pulled apart,the gasket had blown,and leaking exhaust gas into the motor under the spacer.

The gasket had a Ford part no,and was clearly marked "Top" and 'Right" and was made out a thick heat resistant material,the only gasket available to me was a thin paper material, could be fitted either way or either up or down (hope that made sense) - that would never have worked.

The gasket between the carb and spacer was also very thick, and had a Ford part no, made from a typical paper type material.

When I read....

Originally posted by WhiteLakeSkier WhiteLakeSkier wrote:

I also noticed when I took the manifold and carb off that there was two gaskets on top of the spacer, might be the source of some of my troubles?

What do the correct gaskets look like for the manifold/spacer seam and the spacer/carb seam. I want to make sure it is all correct so I'm not doing this again.

Now the intake manifold gaskets, any specifc kind? I got them from pep boys last time for a 1984 ford 302 mustang car.

It would appear he is chasing a vacuum leak, the only thing's he has disturbed are the intake to head's/intake to spacer and spacer to carb, you guys have talked him through the obvious scenario's. and I wondered if WLS had used a standard automotive/aftermarket gasket, but was unsure if the manifold was the same as mine.
At the time (it was around 2002) the gasket was available in the US (I tracked it down via the part no - (saw a picture of it)- from memory it was on marinengines.com or Skidim.
I was told at the time the manifold used was from a 1980's Ford truck. (can't confirm)
To solve the problem at the time I used a steel aftermarket adaptor plate and high temp sealant on the manifold to spacer and a standard aftermarket gasket between the carb and spacer.

Lewy,

Standard ignition system


Posted By: WhiteLakeSkier
Date Posted: April-23-2010 at 2:09am
Alright, tonight I got the other gasket on. The idle actually increased a little. So changing the gasket did nothing. I am at a loss as what to do now. The mixture screws change nothing in my idle, and I have the curb adjuster screw completely taken out and cable disconnected from lever. The timing is set correctly and I sprayed starter fluid all around the manifold and carb to see if there were any leaks. No leaks.

I also turned the mixture screws in all the way, It cut out when I did this. I still have the original gaskets although I don't think I could reuse them. Where can I find a reproduction of the originals? I don't have a clue as to what to try next guys!

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www.correctcraftfan.com/diaries/details.asp?ID=5120&sort=&pagenum=1 - 1961 CC Custom American Skier


Posted By: WhiteLakeSkier
Date Posted: April-23-2010 at 2:11am
The gaskets used were standard holley 4 barrel gaskets, cut to match the old ones by the way.

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www.correctcraftfan.com/diaries/details.asp?ID=5120&sort=&pagenum=1 - 1961 CC Custom American Skier


Posted By: Luchog
Date Posted: April-23-2010 at 6:20am
have you checked the secondaries are fully closed?

spray some w40 on the secondaries shaft and move the mechanism, you could also press it to see if they didnt stuck a bit open.
They have a metal piece that needs to be custom bended for them to top closed, check they are getting fully closed.



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http://www.correctcraftfan.com/diaries/details.asp?ID=2095" rel="nofollow - 1980 Ski Nautique

Commander 351W


Posted By: Luchog
Date Posted: April-23-2010 at 6:35am
91, I dont think anyone's following you yet, cant you get a picture of what you are describing?

The carb gets no warm up from exhaust gases, it uses an electric choke wich is a round device attached to it's side.

The port on the carb spacer connects to the PCV valve on the passenger's side valve cover for gas fumes recovery.
The intake manifold has a port for this too but it's blocked off on most marine applications.

Exhaust fumes are generated in the combustion chambers and leave the engine through the exhaust manifolds, they dont come back into the engine as far as I know...

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http://www.correctcraftfan.com/diaries/details.asp?ID=2095" rel="nofollow - 1980 Ski Nautique

Commander 351W


Posted By: 79nautique
Date Posted: April-23-2010 at 10:54am
I'm betting someone installed an automotive intake on 91's motor and that is why it has a different setup. Don't see why they would suddenly start to use a heat riser passage on the intake when they never did in the 70's and 80's.

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http://www.correctcraftfan.com/diaries/details.asp?ID=756&sort=&pagenum=1&yrstart=1979&yrend=1979 - 79 nautique



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