volvo 250A 1990 REVS DROP

[BMR1953]

Hi all. I'm new here from UK so be gentle with me. Couldn't find a thread to suit so here goes. Have 1990 Sealine Statesman with flybridge, with twin Volvo 250A's, petrols/ 800 hrs. Having major problems with stb'd engine, will start but misfires occasionally. Needs revving to warm up and when warm will run but poorly. Will be smooth at 2000 revs but as soon as throttled down a little, revs drop to 400 and it stalls. Need to rev continually to keep running.
Have new fuel pump and supply to carbs ok. Timing checked. Temperature seems a little lower than port but ok. Any brainwaves before we start stripping and rebulding the carbs PLEASE.
Bernard.

 

[captmello]

Re: volvo 250A 1990 REVS DROP

Welcome!!

It sure sounds like a carb issue. Two on each motor right? I've never worked on that engine but you could consider swapping the carbs from one engine to the other and see if the problem switches to the other motor. At least that would tell you if its a carb issue. I assume the engines share the same fuel and all filters have been checked? With two motors you could swap parts back and forth to trouble shoot, thats kind of handy. Have you done a compression test recently? May be worth while before you start throwing parts at it.

Good luck to you, let us know what happens, okay.

 

[BMR1953]

Re: volvo 250A 1990 REVS DROP

Many thanks for taking the time to respond, I know it's early your end. Yep, twin carbs i'm afraid. Compression test done yesterday, all fine. Ah well. looks like strip and service job on the carbs then, have booked engineer to do when he can.Bernard. Any other ideas most welcome.