Chrysler 75hp lose of power

[bigbz28]

Engine did great last year. This year we lost power after a very short distance. Found that there was a tear in the fuel pump diaphragm (last replaced 2 years ago) Put a new diaphragm in and again lost power after a very short distance of full throttle. I noticed that if I covered the intake of the top carb with my hand that we would pick up speed. Checked for vacuum leaks but don't really find anything. Engine idles fine and revs fine in a barrel but under load it looses power just after plaining out. Could reed valves be the problem? They are the O.E. (1974)

 

[Nordin]

When you cover the intake with your hand you give the carb "choke" and that means less air and more fuel.
Sounds like the top carb do not feed the top cylinder with fuel or right amount of fuel.
As you says you changed the fuel diaphragm because of a tear in it I think you have got some debris from the diaphragm in the top carb.

Try to clean the carbs (all three) because maybe you got more problem if you have debris in the other two carbs too.

When pulling the carbs you can check the reeds.
I do not think you have problems with the reeds, the old ones from Chrysler era will last forever.
They were made from Swedish first (worldclass) class stainless steel.

 

[bigbz28]

Why didn't I think of that! Thanks Nordin! Possible debree from fuel pump clogging the needle valve of the carbs makes since. I did a field cleaning but did not take the valves out. About to perform a complete disassemble and clean of each carb. Will update if I find anything

 

[bigbz28]

Update. Carbs are clean and nothing found in them. I did find a 1 inch piece of the "air cleaner" gasket sitting in the reed valve on the top cylinder. It was not obstructing anything, just sitting there. I also noticed that when I put the control lever at max that the throttle valves were not open all the way. So my dumba$$ tried to adjust the cable instead of the carb linkage and now I can't get it to go back to neutral after full down. Unless I move the distributer back to neutral I can't use the lever to put it back in neutral.

 

[Nordin]

Okey then you found the issue.

You can not adjust the carbs with the remote cables.

Follow parts of the link and sync at the top post of this forum.

Some fast instruction.
1. Set remote control in neutral
2. Adjust the connector for the shift cable so it fits the ball, just to slide it over. Connect it.
3. Retard (move) the distributer all way back.
4. Adjust the throttle connector which is a springloaded connector so you have to preload the spring about 1/4 in to slide it over the ball. This preload is to be sure the shifter has move all the way in gear before the throttle starts to move.
5. Check the butterflies in the carbs so they are fully closed when throttle all way back.
6. Set remote in WOT and check the butterflies in the carbs. If they are not horisontal (they do not need to be exact at horisontal) adjust the length of the throttle rod.

 

[bigbz28]

Ok, linkage is all adjusted and back to normal now. New question. It idles good and revs good in the barrel, but I noticed something. If I hold my hand in front of the carbs the bottom one seems to be pulling in about twice the air as the top 2. Not sure if that means anything but I would expect all 3 to be drawing in the same amount

 

[bigbz28]

Well, I put her in the water yesterday. Fired right up and ran like a champ! Thanks for the help

 

[bigbz28]

One last thing. Does anyone know where I can get the fuel filter gasket that looks like a wagon wheel?

 

[Nordin]

Try Franz Marine, he will have if available new.
Then Ebay is a source.