Author Topic: 4.5HP petteroid exhaust smoke  (Read 3546 times)


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4.5HP petteroid exhaust smoke
« on: December 08, 2008, 01:55:12 AM »
my new 4.5 HP petteroid has just after 2 working hours much carbon deposit in silencer. The engine even smokes when it runs under no load.

Can anyone tell my how to fix this problem? First what I'll do is to check the opening pressure and spray of the injector. Maybe the the delivery time of the injection pump is wrong, too.

I realized that the compression is low compared to my Changfa, but the engine starts after the first attempt.

Can the low compression also be a cause for the massive carbon buildup? Should I remove some of the gaskets between the cylinder block and the crankcase to get a higher compression?

« Last Edit: December 08, 2008, 01:57:24 AM by its-st »


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Re: 4.5HP petteroid exhaust smoke
« Reply #1 on: December 08, 2008, 04:10:55 AM »
At just 2 hours run time it is nowhere near broken in. Run it for a few days with a load and then if it doesn't clear up an investigation will be in order. The Petteroids actually have quite a bit of resistance due to compression. You might want to check the valve lash. Be aware that the exhaust has 2 setting screws, one for the valve lash and one for the compression release. Be very careful with setting the compression release screw AFTER you set the exhaust valve lash or you will have a very high probability of the exhaust valve kissing the piston in a very intimate way!



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Re: 4.5HP petteroid exhaust smoke
« Reply #2 on: December 09, 2008, 03:07:28 AM »
Also recheck that setting after you retork your head and block.
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