Chasing Ghosts?

[cmyers_uk]

I have just winterized the engine and performed a few checks as per the manual. The first was a vacuum check which at 600rpm the needle varied between 16-18 in Hg very fast. The manual seems to say it should be steady and a reading below 18 is the sign of problems. I then checked compression which was 4 cylinders at 150 , one at 160 and one at 170. The engine fires first time and achieves WOT with no problems. Does anybody think I have a problem (mechanical!). Engine is Volvo Penta 4.3GL 4 years old.<br /> <br /><br />Regards<br /><br />Chris

 

[bigbrownbuku]

Re: Chasing Ghosts?

hard to get a solid reading. the best location i have found for vacuum is tapped into the carb spacer. the 20psi difference is a sign your engine is wearing. a leakdown test would help to pinpoint the problem.

 

[Don S]

Re: Chasing Ghosts?

Sounds to me like the owner is having a problem putting the boat away for the winter <br />Compression sounds fine, the vacuum reading sounds more like a gauge vibration than a vacuum problem. <br />Next spring after you run it, do another compression test, then tune it up, new plugs, cap rotor, check the timing and then do another vacuum test.<br />Make sure when you do your compression test you have the throttle wide open. Here is the recommended practice for compression tests, it's from Mercruiser, but the same as Volvo and it all comes from GM.<br /> Compression Test Procedures

 

[cmyers_uk]

Re: Chasing Ghosts?

BenC , Thank you I removed the pipe that goes to the PVC value and took the vacuum off the carb at that point which may be part of the problem as the PVC valve then wasnt getting any vacuum I will look at where the carb spacer is or indeed what it is! and see if that gives me better readings.<br /><br />Don, <br /><br />I think its a case of too many tools but not enough knowledge to use them . I hadn't done the compression test with the throttle wide open so will repeat in the spring following your guide. I also have never in 4 years changed the cap rotor or checked the timing which seems the perfect excuse to use my latest ebay purchase a snap on timing light!. I think I am going to leave it alone now its all fogged up and when I prepare for the new season recheck the vacuum. It runs to sweet for anything major to be wrong (he says hopefully).<br /><br />As ever thanks for all the advice, Im having fun here and hopefully saving a few pounds.<br /><br />Regards<br /><br />Chris

 

[KaGee]

Re: Chasing Ghosts?

Originally posted by Don S:<br /> Sounds to me like the owner is having a problem putting the boat away for the winter

Any cure for that one Don? Home remedies? Supports groups?<br /><br />I NEED HELP!!!!<br />

 

[Don S]

Re: Chasing Ghosts?

Play with this simulator for a while, you can crank up the waves and wind and have a grand time and you don't have to put fuel in it either. <br /><br />Boating Simulator

 

[cmyers_uk]

Re: Chasing Ghosts?

Don,<br /><br />Great but wheres the strip down the engine simulator, I like the idea of a virtual spanner, and no need to buy new gaskets everytime I remove something for the hell of it!.<br /><br />Regards<br />Chris

 

[KaGee]

Re: Chasing Ghosts?

Ohhhhh yessss! Thank you Doctor Don for that prescription. Got my fix for the day and I feel sooooo much better!<br />

<br /><br />How long will that Merc outboard last @ 7000RPM ?

 

[Don S]

Re: Chasing Ghosts?

Till the computer crashes <br /><br />Have you cranked up any good storms with 50 MPH winds and 50 Foot waves, thunder and lightning, and rain and ........... You know, good old Alaska boating weather.