Won't Idle below 1000

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.

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.

Well It must be RH then. I shall readjust timing then

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?

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.

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.

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....

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.

I think what you are refering to is the PCV port, wich connects the carb wedge plate to the valve cover.

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.

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....

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

The gaskets used were standard holley 4 barrel gaskets, cut to match the old ones by the way.

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...