Carb Problems???

[foxridermx]

I have a 1986 Bayliner Capri 225E Volvo penta with a 305cid chev engine. I am having problems I think are with the stock Rochester 4 barrel carb. the engine starts and idles but there is a dead spot at 3000RPM where it back fires, spits,farts when applying throttle if I slowly increase the throttle sometimes I can coax it over this dead spot but mostly it misses and back fires at 3000 RPM. I don't think the choke is working properly and the secondary butterfly doesn't seem to open all the way.(even when I can coax it up to full throttle) I have had my uncle (a mechanic) rebuild it twice and set the jets etc. but it still has this problem. what is a likely cause for this? could the problem be with the timing or ignition and not the carb? how could I test that theory? I was going to try a Edelbrock 1409 carb on it and was wondering if this Edelbrock is a direct replacement for this engine? or do I need a different manifold or base plate? Thanks for any help everyone

 

[jerryjerry05]

Re: Carb Problems???

Welcome,fill out the profile,location.
You might be close to someone who can help.
I believe the Edelbrock will need an adaptor plate.
Sounds like it's starving for fuel.
You change the filters?
Ethanol? It delaminates old hoses and can cause them to collapse.
There is a small filter inline by the fuel pump.
Usually by now that filter's rusted/rotted away and been replaced. Maybe it's clogged.
The pickup in the tank could be picking up stuff/clogged?
The pickup "might" have a screen on the end it could be blocked.
The vent line to the tank could be blocked?
Bee's/wasps like to build nests in the hose.
Look for any restrictions.

 

[captmello]

Re: Carb Problems???

Like jerry said, it does sound like its starving for fuel. The secondaries most likely will never open completely on a smaller motor like yours. I'd also check the ignition timing like you mentioned and check the dwell. When was the last time you replaced the points?

 

[foxridermx]

Re: Carb Problems???

it has an electronic ignition no points
we have changed the fuel lines and filter and water seperator. I am pretty sure its getting gas but will have to check for sure. thanks guys. will reply to post with more info.

 

[Ilovevolvo]

I have a Volvo Penta to 225e I bought for cheap it does not have original distributor. I have a no spark situation I looked up original distributor ,but volvo says it’s discontinued can anyone suggest a GM replacement perhaps the Volvo Penta number for distributor is 841069

 

[kenny nunez]

I have a Volvo Penta to 225e I bought for cheap it does not have original distributor. I have a no spark situation I looked up original distributor ,but volvo says it’s discontinued can anyone suggest a GM replacement perhaps the Volvo Penta number for distributor is 841069

Sierra marine #18-5480, this is a complete kit with the coil and wires.