My 1972 85HP Chrysler: Running better but more questions

[turtle1173]

Hi everyone,<br /><br /> Thanks for all the help that everyone has given to me lately about this engine. I put on the new head gasket today and torqued it accordingly, then went out to the river. I ran the engine on the trailer and was able to verify all cylinders were hitting by adjusting the idle mixture. I ran it for probably 15 minutes. Then pulled out and checked my compression. It was: #1-105, #2-90, #3-110 I then re-torqued the head but didn't recheck the compression.<br /><br /> OK, here's my questions now. In order to start the engine, I have to squirt gas into the carb throats. Then it starts up. Is this a carb problem? I had dissassembled the carbs and used carb cleaner on it, then reassembled. I have also replaced the fuel pump.<br /><br /> OK, when I put it in gear, often it will die. Sometimes it won't die (barely) and it will run in forward (on the trailer) until I get up past 1/4 throttle. Then it will start to sputter and die. Would this also be carb related?<br /><br />Thanks for you suggestions.<br /><br />Shane

 

[12Footer]

Re: My 1972 85HP Chrysler: Running better but more questions

Try taking the gas cap off when it does this to see if performance improves. If it does, you have a clogged or closed tank vent (on portable tanks, this is the little screw dealy in the middle of the cap).<br /><br />If performance does not improve, squeeze the primer bulb to see if it is firm.<br />If not, and performance improves when you squeeze it, you have a restriction in the fuel pick up (tube,hose,primer bulb, all the way to the fuel pump), or an air leak in that pick up somep[lace, or defective fuel pump, or low compression (pump uses compression to operate it).<br />The compression is low, but should be sufficiant to run.

 

[turtle1173]

Re: My 1972 85HP Chrysler: Running better but more questions

What would cause it not to start unless I squirt premix directly in the carbs? I've squeezed the bulb enough to where it shot out of the vent on the top carb.<br /><br />Thanks,<br /><br />Shane

 

[Terry H]

Re: My 1972 85HP Chrysler: Running better but more questions

You have a electric choke on that model. Make sure it's working properly, won't start very easily without it...just a Thought

 

[turtle1173]

Re: My 1972 85HP Chrysler: Running better but more questions

OK, my choke shutters do not close all the way. When choke is engaged, there is probably a 3/8" gap on the bottom. Would that be enough to not allow it to start while cranking? If I adjust it so that they do close all the way, then they are not horizontal when open. Do they have to be completely horizontal when open or does it really matter if slightly tilted?<br /><br /> Now, what about the "dying when I shift it into gear" issue? It dies 9 times out of 10 when it is shifted.<br /><br />Thanks again,<br /><br />Shane

 

[scotiany]

Re: My 1972 85HP Chrysler: Running better but more questions

I assume that you have Tillotson WB carbs. Did you diassemble them and soak them in Carb cleaner or gasoline and then blow them with compressed air and reassemble. Also did you make sure floats are level with bowl flange,

 

[turtle1173]

Re: My 1972 85HP Chrysler: Running better but more questions

I do in fact have the Tillotson WB carbs. I disassembled them and sprayed them down with Carb Cleaner then blew them dry with compressed air. After I had everything hooked back up, I was looking through my manual and noticed that the nozzle inside the turet is supposed to come out. So I didn't take that out to clean it. Could that possibly be my problem? Also I didn't use the carb cleaner where you disassemble and immerse it in the cleaner overnight. This was carb cleaner in a can. I did not mess with adjusting the floats any. Perhaps I need to go back over it more thoroughly.<br /><br />Shane

 

[jim dozier]

Re: My 1972 85HP Chrysler: Running better but more questions

Choke should shut tight when on and should be completely open (horizontal) when off. If it isn't doing both there is something amiss with your linkage. Also idle speed should be set with the engine in the water in gear not neutral. If you have the idle mixture set right and not too lean, and you have the idle speed set right, and the choke shuts tight it should start and idle much better. I think from your description the choke operation is the key to your problem.

 

[turtle1173]

Re: My 1972 85HP Chrysler: Running better but more questions

Jimd,<br /><br /> I guess I need to mess with that choke linkage a bit to get it to work right.<br /><br /> The choke wouldn't affect it dying when I place it in gear, right? It idles down nice but when I push it into forward, it just conks. Are you suggesting that the idle speed may have something to do with this? Just trying to clarify. Could the timing possibly be an issue with this?<br /><br />Thanks again,<br /><br />Shane

 

[oldboat1]

Re: My 1972 85HP Chrysler: Running better but more questions

It sounds to me like you may be in line for rebuilding the carbs. Squirting cleaner in won't clear the passages (or should probably say won't necessarily clear the passages).

 

[12Footer]

Re: My 1972 85HP Chrysler: Running better but more questions

DO NOT emerse this carb in carb cleaner unless it is stripped to bare metal. Any rubber or styrene ,or plastic will be devoured by the solvent (like the rubber tip on the float needle, float needle rubber seat,ect.<br />That stuff is viscious..Good, but viscious. Use carefully.<br />But Scotiany is correct to recommend a good carb cleaning. The fuel comming out of the carb indicates a stuck open, or leakin-by float needle, or sunk float, or unlevel motor. Try thumping the level carb bowl with a screwdriver handle while somebody keeps the primer firm,and see if it quits. If it does, you may not need to tear into the carb.<br />The choke nbeeds to be adjusted to where the butterflies completely cover the throttle body. You aren't getting a good choke until it can't get air.

 

[turtle1173]

Re: My 1972 85HP Chrysler: Running better but more questions

You bring up an interesting point that I definitely didn't think about. The launching ramp is fairly steep. I still had the boat tied to the trailer, so it wasn't floating when I was backed into the water. Just thinking about this, that would cause the floats to behave in a different manner because of the incline. That might have the floats shutting down when I shift it into gear, thus the engine not getting gas.<br /><br /> Am I grasping at straws or does that sound reasonable??<br /><br />Shane

 

[jim dozier]

Re: My 1972 85HP Chrysler: Running better but more questions

How an engine idles in neutral is irrelevant. If it won't idle in gear it isn't idling properly. First make sure the idle speed is set to the appropriate rpm in gear in the water. Then set the mixture. Then fix anything else like your choke. And if that won't get it you need to rebuild the carb.

 

[scotiany]

Re: My 1972 85HP Chrysler: Running better but more questions

12 Footer, You're right of course. I've taken my Tillotson down completely and I can't find any plastic parts. Do you think that are some hiding in some obscure orifice on that carb?

 

[Terry H]

Re: My 1972 85HP Chrysler: Running better but more questions

Turtle...sounds like all you needs to do is a complete link & sinc...and get that choke adjusted right...double check the distributor timing, all very simple if you do it by the book, you should be running fine...just a Thought

 

[turtle1173]

Re: My 1972 85HP Chrysler: Running better but more questions

12Footer?? Would the ramp have anything to do with this?<br /><br />Shane