FIRST POST

I suppose it depends on where you check, how spongy the lines are, how good your needle and seats work, seal health in the fuel pump, etc.   Having a bit of residual pressure would seem to be about right with a mechanical pump with check valves vs an electric pump with radial vanes. It won't be an issue with a jet change, you drain the bowls the floats will drop and once a very slight amount of fuel comes out of the line into the bowl the pressure will be zero. Unless the motor is turning over you aren't going to see fuel leaking everywhere.   

Good luck, and if it is not the carb that was causing the problem take a look under that distributor cap and make sure the cap/rotor are good and that the mechanical advance mechanism is doing what is should be.

I had a similar issue with my 351 hitting a wall at 4000rpm. My distributor advance mechanism was stuck. I freed it up and added a couple drops of oil, winds out to redline fine now.

Check your advance mechanism and check/set your timing.

You can rev it higher briefly. Long enough to check timing at 3k+ (keep rolling it up until it stops advancing).

What did you have for initial and at 2500? The described issue could be fuel or ignition... but is more commonly the latter IME.

I don't see any mention of whether you have points or electronic ignition.

If you have points, the attached link is good reading.

If you don't have points then none of this matters   

It deals with a strap for the PCM points that sometimes people forget to install and it let's the engine run good up till about 2500 rpm, then you get point bounce and it won't rev any higher.

Some brands don't have or need this strap due to their construction, some brands do. PCM is one of them that does need it.

link

I can be pretty good at adjusting a set of points wrong so that the engine starts good, idles smooth and sounds and runs like crap at a couple thousand RPM or so and all it takes is an adjustment to get the dwell/gap right and it runs good again so you might want to check that too..

Oldskidude wrote: Keno - You posted a pic of an oil pan that I think you had for sale that had bubbles in the paint near the pan rail. This pan also has the same bubbles only larger. All I can think of is it was caused by heat. Am I correct?   Are these bubbles anything to worry about? .

If it was this picture, it was from a thread with a comparison of an original and an aftermarket pan.

I figure it was due to a combination of heat and not so good adhesion. It seems to be a very thick epoxy type paint.

I haven't worried about it.

KENO wrote:

Dan

Here's a quote from a recent post about how to post pictures.

8122pbrainard wrote: Jon, If you are trying to post pictures from a mobile device, it's not easy and some have found it impossible. From a laptop you will want to use the "post reply" or the "full reply editor". Then you will see an icon of a tree with an up arrow.Clicking it will bring up a browse box allowing you to select anything off your computer. Give it a try.

As far as the coil goes, with your points any run of the mill 1.5 ohm coil for use with an external resistor will work just fine The coil and resistor should add up to about 3 ohms

Go to NAPA or your favorite parts place and tell them you need a coil for a 67 Ford Mustang with a 289 and about 20 to 25 bucks later you'll be all set.

Yesterday (Friday), we worked on the boat. First chore was to document the timing advance by bringing the revs up slow. It advanced to 2500 RPM and the light waverd until it got past to maybe 2700 or 2800 RPM and then smoothed out again. At 3500 RPM the timing was 28 degrees. It sure seemed like electrical and not carburetor, thanks Mr. Brainard. Well, lets open up the points just a little, so we set them at 20 thou. The timing was smooth but could't tell at what RPM as the tach went wacky. Popped the cap again and just looked for anything out of place. This sounds crazy but, the screw that holds the points down is not tapered round like the screws that hold the plate down and looked to be touching the points. My son filed the circumference of the screw head maybe 8-10 thou to see what would happen. Tach worked as it should and timing was smooth to 3500 RPM and 28 degrees. His house is literally three minutes to the Scioto river, where we used to have a dock and skied there regularly, so off we went. It started fine, idled fine and ran great up to 3600 or 3700 RPM and 35 MPH, then broke up as it did at 2500 RPM on our first outing. Gotta be electrical, but what. As crazy as it sounds we're thinking the points screw is interfering with the points, so the plan is to put a socket head or button head screw in the points, something that has definite clearance and try it again today. Does this even sound possible that someone over the years replaced that screw with something different that would cause this problem???

Thank you Mr. Keno. Having not looked at points since probably the 1970's, these just didn't look right to me. This screw is definitely not a round head.   The screw threads are at least 5/16" long with a barrel head and the point arm looked to be touching the screw head or if not touching extremely close. I've got to guess someone lost the original screw and just replaced it with something that fit. We are going to replace the screw today and adjust to .018 and check the timing again. So, I've got two things going through my head 1. The point arm was touching the screw head or 2. The screw is too long and interfering with the weights. Does 28 degrees at 3500 RPM sound reasonable to you.

I'm BACK! I haven't posted in a little while, you guys probably thought the boat was fixed, NO WAY! We tested it on the river a few weeks ago, seemed to run fine up to 3500 RPM then broke up and nosed over. My son had a chance to take it to Sand Lake, MI for the Fourth of July Holiday. He thought that if he stayed under 3500 RPM he could enjoy it for a little while instead of working on it all the time. Wrong. With three adults in the boat towing a large tube with three children it was missing at 2000-2200 RPM. After a couple of hours of constant tubing it started missing at any RPM so he put it on the trailer and brought it home. Saturday we checked the timing and dwell, OK. Then we pulled the plugs, refrigerator white, too lean. Number one cylinders plug showed signs of detonation. We ran a compression test (125 low and 140 high) and fattened the jets by two numbers and put in a new set of plugs. Today we pumped out the fuel tank using the fuel line which left a small amount of mixed old/new fuel in the tank then added five gallons of fresh. At the end of the line going into the gas cans he put a new clear fuel filter to see if any junk was in there, just clear fuel with no debris whatsoever. So, this boat has new points, condenser, rotor, cap, coil, 8mm wires, Quick Fuel carburetor, fuel filter/separator, ignition switch, wiring at the breaker panel (no daisy chain), start relay and ballast resistor. Fired it up, started with just a touch of the key and idled great, and let it warm up a good while (150 degrees) and slowly advanced the throttle to check timing advance. Started at 10 degrees initial, at around 20 degrees the light fluttered, moved back a little then went on to 27-28 degrees at 3500 RPM. The tach also fluttered when it was missing, the dwell meter stayed a constant 30 degrees through the test. The only electrical item that is not brand new is the distributor (original Prestolie). My son can buy ethanol free fuel at work, is that an option? Or, is it time for a new DUI or MSD distributor? Thanks in advance for any suggestions, Dan

Could this be a Prestolite distributor that needs the extra spring on the point set??

The pics didn't load. Click the icon of a tree with an up arrow. Click the pic and click open???

IT'S FIXED, I think. We took the gray tach wire off and started it up. Ran terrible, maybe even worse than yesterday. Put the tach wire back on, still terrible. Hooked up the timing light to each cylinder, they were all missing. We just stood there and stared at all these new electrical parts and wondered what the heck. I then said , hey remember when we put in the points and condenser. The condenser lead was about four inches long and it just baffled us as to why so long. Having never seen a condenser looking like that, I wrapped that sucker back and forth to make it fit. I know your laughing right now KENO! Fired up the new tune up and the tach was reading about double of what it should. Somethings wrong. Lets try to cut the condenser lead and drill a hole in it to attach it. Pulled off the blue insulation and what do you know, it already has a place to shorten it, I had no idea. Did that and it ran kinda OK. So tonight, let's just put the old condenser back on and see what it does, it's the only thing that I can think of. Viola, no miss, runs better than it ever did. Checked the plug wires again with the timing light, no miss. Ran it up to 4000 RPM, timing was smooth all the way. We must have fried the new condenser.
We will take it out later this week for a test run and I will report back.

One more question though, a couple of you guys mentioned the extra strap on the points and I replied yes it was there, well maybe not. I will try to load a pic of the points that we took out and they look the same as what we got from Skidim but maybe I'm missing something. I want to graciously thank all of you for your input on my issue. Dan

People like to say that"they don't build points and condensers like they used to".

Now you might agree with that statement   

Well, we took it to the river Saturday and it performed flawlessly. The fastest we went was 38 MPH at 3800 RPM, there was still some throttle left but we were a little gun shy with all of the aggravation that we previously experienced.

We took the plugs out for inspection, still refrigerator white. In our race car engine we like to see a light tan color. I searched this forum for a colder plug and found a post stating Autolite 24, 25 or 26 is the preferred spark plug for these engines with the 24 being the coldest. If anyone reads this that has a Quick Fuel 650 CFM and has rejetted it I would appreciate knowing what size jets you installed. In the meantime, we will increase the fuel to the idle circuit to see what happens. Thanks again guys.

Oldskidude wrote: If anyone reads this that has a Quick Fuel 650 CFM and has rejetted it I would appreciate knowing what size jets you installed. In the meantime, we will increase the fuel to the idle circuit to see what happens. Thanks again guys.

I have a QF M-650 on my 1994. Most of my boating happens at 4,400 to 6,000 feet of elevation, so I re-jetted the carb as shown below:

QuickFuel M-650 Carburetor - Stock settings
Primary Main Jet 71 / Secondary Jet 78
I dropped the primary and secondary jets by 2 sizes for altitude. I may drop both the primary and secondary another 1 jet size as the plugs are still reading a bit rich.

Also, the idle circuit was a bit too rich. To achieve the highest vacuum, all 4 idle mixture screws were leaned-out almost 1/2 turn.

JQ