volvo nightmare

[bobobobbers]

heres the deal: 4 cyl volvo penta (ran great last year and was winterized as well) starts and idles fine, revs up great in netural. UNDER POWER it loses power badly and will not plane the boat. Plugs show black dry deposit (rich condition). Also top rpms are about 1/2 of what they should be.<br />Here is what we have done:<br />New plugs, new plug wires, new points, new condenser, new cap. To be safe we hooked up another small tank with fresh fuel by passing the fuel in the tank and installed a new fuel pump. Timing is on the money, dwell is great, and the distributor advances in netural as it revs up to the required specs. Have checked all the electrical connections. Besides spending a lot of $$ on parts so far..I have wasted several saturdays trying to fix this.....I am now lost

 

[hoot]

Re: volvo nightmare

try replacing your ignition coil.

 

[cobra 3.0]

Re: volvo nightmare

Is your starter disengaging after startup. It could be hanging on the flywheel.

 

[wildcat 01]

Re: volvo nightmare

I have a 1987 4cyl volvo, I was haveing pretty close to the same problems as you. I replaced the same parts as you did with the same results. After many weekends of being rather unhappy with the whole thing I finally took it to a mechanic. What he found was the new condenser wasent working properly, the lifters were out of adjustment as well. Your problem sounds like its not getting enough spark to burn the fuel your dumping into the cylinders...hope this helps...good luck.

 

[Dunaruna]

Re: volvo nightmare

Hi bob bobbers,<br /><br />What engine are we talking about (aq####)?<br /><br />Aldo

 

[bobobobbers]

Re: volvo nightmare

i was thinking along the same lines with an ignition related (or low ignition power) situation. I forget off hand but i think it is either an aq 130 or 140, single barrel down draft carb (and yes we also had the carb rebuilt!)...Hope the coils thing works..here come another saturday in the ol' work shop instead of on the water! .....<br />keep the ideas coming..i have way to much invested in this to stop now! hahaha (arrrrgh)

 

[Dunaruna]

Re: volvo nightmare

Bob,<br /><br />Let me throw another possibility into the ring.<br /><br />Timing belts can and do slip a tooth as they wear (not uncommon on old volvos), the symptoms are similar to what you describe.<br /><br />The problem is, aq130 is a push rod engine and the aq140 is OHC. You decide.<br /><br />Aldo

 

[wally jr]

Re: volvo nightmare

what year is your motor? i have a 1984 4 cyl volvo and went through the same exact problem.. after all new parts and doing the timing etc.. i had another mechanic do a bay test with me and he advanced the timimg..i really dont know much about these things and i've advised advancing before with good results.. it was explained to me that motors get tired... a real slight advance made a big difference and i enjoyed the boat for the rest of last season..pls post when you find out or resolve..thanks..

 

[wally jr]

Re: volvo nightmare

you should also look at your propeller and make sure its ok..

 

[kayakndave]

Re: volvo nightmare

Bob....I'd look at the carb again. Just because it was rebuilt, doesn't mean it's not the problem. I had this very same problem (4cyl. Volvo, twin solex carbs) and the problem was with the secondary carb. It ran great on the trailer, but take it out and put it under pressure, and it would run like you were pulling a bulldozer. Make REAL sure all the jets are clean, you have a good accelerator pump, and the float is set at the right level - Good Luck!

 

[wally jr]

Re: volvo nightmare

in my volvo shop manual it says to chk a couple things...damaged propeller-bent rudder-misalignment ( thats engine to the stern)... i had the same motor (single carb) and replaced virtualy every part including ignition parts and still had the same problem you had.. when the timing was advanced it was fine.... if you need, i could send you some of my manual... i'm not saying dave is wrong..take the air filter off and make sure your jets are shooting fuel... if i had to bet on other advise but my own i would go with DUNARUNA... he seems to be one of the kings of troubleshooting.. try the advance......good luck

 

[wally jr]

Re: volvo nightmare

sorry, one more thing. wgat i mean by the "advance" is turning your distributer a hair... try it, it;s takes you 1 min..

 

[fish393]

Re: volvo nightmare

I have a aq170 volvo and have had the same poblems.Was told to throttle the boat until its starts to choke and then cover the cabs one at a time with my hand and if it was a carb it would take off when I got to the bad carb. Did that and the boat took right off.good way to check the carbs I have three.

 

[bobobobbers]

Re: volvo nightmare

ok guys...(and gals)..going down to the shop in the am to try a few things ya'll told me....something has gotta work!

 

[Dunaruna]

Re: volvo nightmare

J.R.<br /><br />I appreciate your thoughts but I'm afraid your wrong. I know early volvos and thats IT! The only other thing I know about boats is that the pointy end is the front .<br /><br />I'm a mechanic, put a problem in front of me that I can see and touch and I will fix it. Type a problem onto a computer screen - my brain turns to mush. <br /><br />People like Bondo, Trent and rodbolt are the true masters of diagnostics via the screen, they know from experience. I love boats and boating,I read every thread on i-boats and someday hope be helpful to others. Until then, I'll respond to early volvopenta questions and hopefully not stuff up.<br /><br />Aldo

 

[placebo]

Re: volvo nightmare

Bobbers, I will throw my 2 cents into the ring as well, and suggest you look at the carb again. Like Fish, I have 3 of these babies on my boat, and when they work, they work great. When they don't, I am not happy. The good thing is these Solex carb's are easy to clean, you just need to be CLEAN. Take it off the boat and clean every thing with gasoline and a soft bristle brush. You will not believe the difference.<br /><br />Hope this helps. David

 

[fish393]

Re: volvo nightmare

Just got back from cleaning the other two carb just like old volvo said and gained 6 mph went from 32 to 38 mph.Pinging has disapeared as well seems like a new engine.Second time looking at the carbs.

 

[bobobobbers]

Re: volvo nightmare

well did not make it down to work on the boat last weekend..wife did the "your not going to work on that dam boat again" routine....so anyway bought a coil to put in...somebody told me to take a look at the ballast resistor???????<br />any input on this one?