3B compression test results (1 Viewer)

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I just got home from Cruiser Rica (Costa) and my new compression gauge was here. so I got the 3b in the 80 bj40 done Not great #s but the I thought I would have one real low because of all the blowby gasses but they were even. But on the lower side.

hot #1 350 #2 345 #3 355 #4 360

wet #1 410 #2 400 #3 400 #4 390

I stopped there since it is evedent that rings are going. I was told this was a 200k engine and I do not know if it was cheap rebuild or what.

Rebuild in the near future.
 
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cruiser_guy said:
You should have stopped by! Or did you fly?
We flew, We have talked of Driving down someday, but a little worried about our USA status, Candians are much better recieved from what we hear in some countries around your area.

But if we do we will stop by.
 
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crushers said:
the wear seems nice and even for a 500,000 km, really low for a 200,000 km engine..
cheers
I am very suprised about them being even, this engine has heavy blue blowby at startup and continues from then on. I thougth it would be one cyl with broken rings.
 

crushers

post ho
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remember that oil rings and compression rings are 2 different things. did you check your valve seals? the valves can still seat properly but the seals can be cracked or missing...
cheers
 
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crushers said:
remember that oil rings and compression rings are 2 different things. did you check your valve seals? the valves can still seat properly but the seals can be cracked or missing...


cheers

Next on the list, but would valve seals show in the blowby ? there seems to be no oil smell out of the exhaust before I vented Crankcase venting into the intake before the turbo now to avoid funny looks and smells, there is considerable oil showing in the intake system to the point of leaking out of the intake to block gasket.

My 81 blows blue out he exhaust and no blowby 376k km's
so I am thinking oil rings or valve seals there.
 

crushers

post ho
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is there any lines from the turbo, crossover pipe, throttle body to the crankcase, tappet cover, etc where you could be pressurizing the cranckcase with turbo pressure hence pressurizing the cran case forcing oil past the rings?
cheers
 
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No place for the boost to go into the Crankcase Execpt the oil return line from the turbo and that is very unlikely.


Here is the comp on my 81 3B It also has some issues. 345k kms

#1 400 hot 460 wet (carbon ??)

#2 340 395

#3 340 395

#4 340 370

Looks like to me that I could do the valves and increase the comp some but not worth it, looks like a rebuild soon on this one it does give out blue smoke but no blowby.
 
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Tapage said:
this engine have a thermostat .. ?

yes it does but not working well but I got it up to temp with covering the Rad with cardboard and driving it.

Did you see something in the #s ?
 

Tapage

Club 4X4 Panamá
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mallred said:
yes it does but not working well but I got it up to temp with covering the Rad with cardboard and driving it.

Did you see something in the #s ?
I thought the thermostad are very very important thing in a diesel engine ( maybe in a gas engine also ) your diesel engine require a certain amount of temp to get proper combustion.

If your engine are to cold, internal parts are tooo tight
 

crushers

post ho
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actually the oposite, cold = too loose
heat expands metal...

never mind i think i get what you are trying to say, too tight=too small...

cheers
 
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