FL120 compression test

Sealife · Dec 20, 2018

Any interested:

Made an adapter out of an old spare injector. Cut off tip, plugged supply line with epoxy, drilled out internals, drilled and tapped return to accept compression test equipment. Worked great.

DavidM · Dec 20, 2018

And what were the results? Many knowledgeable diesel guys believe that compression is a worthless indicator of ring and valve sealing. Blowby is much more indicative.

David

yamabuki · Dec 20, 2018

Pressure test

djmarchand said:
And what were the results? Many knowledgeable diesel guys believe that compression is a worthless indicator of ring and valve sealing. Blowby is much more indicative.

David

Am soon going to pressure test one of our Perkins 6.354 (removed injectors for service etc) what is blowback and how is it determined.

Sealife · Dec 20, 2018

Blowby is a generic indicator of all cylinders. I wanted a cylinder specific test to compare to factory specs. This wasn’t a “general engine health” test.

Don’t want to get into all the theories.....just wanted share a an adapter option.

Airstream345 · Dec 21, 2018

nice! you're not the only one using "dummy" injectors for compression/leak down testing. I've learned a lot watching his videos

bgillroy · Dec 21, 2018

Great video thanks .

Forkliftt · Dec 29, 2018

Great advice Sealife!!
Noted-

yamabuki · Dec 29, 2018

Compression test

Airstream345 said:
nice! you're not the only one using "dummy" injectors for compression/leak down testing. I've learned a lot watching his videos

Thanks for video, really helpful.

ctjstr · Dec 29, 2018

holy buckets, that's about as complicated a description of a leakdown test as I've ever heard.

Unless there is something special about diesels, I'm certainly not agreeing with him suggesting that you would be ok with leak down close to 20%. (unless I misheard what he said). The few I've had have always been below 10. Curious if anyone has had a leakdown test done as part of a mechanical survey and what results the survey showed as "acceptable".

BruceK · Dec 30, 2018

This is "driftish", but info for FL owners. The header tank downtube tends to get eaten by coolant, and leaks. Solution is to weld on a replacement tube. On one of mine, the weld job failed,becoming a minor leak,at the right height to run into and around the head/block joint. Thus mimicking a failed head gasket coolant leak. I even bought a head gasket($100 shipped, not too bad at all), which now goes into the parts box.

FL120 compression test

Sealife

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DavidM

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Sealife

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yamabuki

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