problems with chevy 305 in 1989 bayliner

[djquick_silver]

The problem that I am having is that it won't get above 2900 rpm and when I pull off plugs 1,4,6,7 all together there is absolutely no change in the running (ie: doesn't drop any rpm) but if i put those 4 back on and pull the other 4 wires it progressivly drops in rpm til it dies. The cap, rotor, wires, plugs, condensor, and points have all been replaced and i seem to have spark at the ends of the wires with a spark tester. Is it common for a chevy 305 to run on only 4 out of 8 cylinders or is there some form of failsafe built into the motor so that it will get you back?<br /><br />Any help from anybody would be greatly appreciated.

 

[Rick Byers]

Re: problems with chevy 305 in 1989 bayliner

I am speaking as an automobile technican. Based on your description I would say you have either a Carburator problem or a vaccum leak. Cylinders 1-4-6-7 are the first and last cclinders on the left bank and the center 2 cylinders on the right bank. Have seen this problem before on 2 barrel carburator powered 305s that have sat unused for awhile. They plug up internally. hope this helps. Rick

 

[djquick_silver]

Re: problems with chevy 305 in 1989 bayliner

Is this also a problem with the 4 barrel carbs? This motor has the Rochester 4barrel Q-Jet on it and I have heard that they aren't very good carbs. The plugging up internally is in the carb itself?<br /><br />Thanks for your reply anymore help would be extremely appreciated i'm tired of fighting with this money pit.

 

[Trent]

Re: problems with chevy 305 in 1989 bayliner

To rule a few things out. Do a compression check. Both wet and dry methods.

 

[djquick_silver]

Re: problems with chevy 305 in 1989 bayliner

I checked things out and I have spark and good compression in all cylinders. I checked the carb and one side of the main jet doesn't seem to start to flow at all until about 2600rpm and then not very much at all. When I pulled the carb off the runners were wet on one side and dry on the other. So thank you for your fast replies I think that I should hopefully have it all cleaned out and running by the weekend. Gotta Go Fishin'

 

[Rick Byers]

Re: problems with chevy 305 in 1989 bayliner

Also a problem with the Q-JET carb. they plug up real bad. A good clean out after disassembly should do the trip. Let us know what happens. Rick

 

[djquick_silver]

Re: problems with chevy 305 in 1989 bayliner

I've fixed the fuel problem and it seems to be running on all 8 cylinders but I can't get it to idle no matter what combination of adjustments i do.But on the plus side i seem to be able to get it over 2900 rpm now. Any other common problems with these that I may be missing somewhere? As you can tell i'm not a chevy person

 

[Bob_VT]

Re: problems with chevy 305 in 1989 bayliner

Recheck your firing order. You have been doing a good deal of ignition work and a slight mix up is not uncommon. Check your timing. An engine will run even if wires are out of order but never attain WOT.<br /><br />Bob

 

[djquick_silver]

Re: problems with chevy 305 in 1989 bayliner

Thank you to all that helped me solve this problem. I went over things today again checking firing order and all that and thats when i noticed a small drip under the carb it seems that in all my let's not loose parts i forgot to take the washers back off the studs where i put them to not loose them which caused a pretty large vacum leak 1/8 inch anyways, But it runs well now that it is removed from the equation. The only other problem we're having now and it is just a recent occurance is it is extremely hard to shift and when you put it into reverse you have to shut the engine off in order to get it back to nuetral. There is a new short shift cable and the leg was just rebuilt by a local repair shop so it has almost no hours on it due to the previous problem. Has anyone else had this problem? It is an OMC Cobra leg.