Plug Found In Bottom Of Case

78 STROSEK · 78 STROSEK's Garage

I HAVE A 77 2.7 ENGINE THAT WAS RECENTLY OVERHAULED, BUT HAD LOW OIL PRESSURE WHEN HOT. I TORE THE ENGINE DOWN TO FIND THE PROBLEM AND FOUND A SMALL ALUMINIUM PLUG LAYING LOOSE IN THE CASE. I THINK IT MIGHT BE AN OIL GALLEY PLUG. THAT WOULD EXPLAIN THE OIL PRESSURE PROBLEM. BUT I CANT FIND WHERE IT CAME FROM. ANYONE KNOW WHERE THE PLUG SHOULD BE. IT IS THE SIZE OF A DOWEL PIN.

john walker's workshop · 03-01-2005, 01:38 PM

end of the intermediate shaft?

78 STROSEK · 78 STROSEK's Garage

I DONT FIND ANYTHING MISSING ON THE SHAFT. ALSO IT IS TO LARGE TO FIT THROUGH THE HOLE IN THE OIL PUMP DRIVESHAFT, SO IT WOULD HAVE STAYED IN THE DRIVESHAFT.

racing97 · 03-02-2005, 06:44 AM

If it is approx 7 to 8mm dia it is possibly a crank oil passage plug. If the crank was repaired and Heat Treated during the rebuild, the plugs visable on the Rod journal end Counter Weight side will loosen up and fall out. They should be tapped and replaced with pipe plugs. Check and see if the rebuilder had the crank Heat Treated.

Best regards

ChrisBennet · ChrisBennet's Garage

Quote:

Originally posted by racing97
If it is approx 7 to 8mm dia it is possibly a crank oil passage plug. If the crank was repaired and Heat Treated during the rebuild, the plugs visable on the Rod journal end Counter Weight side will loosen up and fall out. They should be tapped and replaced with pipe plugs. Check and see if the rebuilder had the crank Heat Treated.

Best regards

Wouldn't the plug in the crank be steel instead of aluminum?
-Chris

Crowbob · 03-02-2005, 08:14 AM

78 Stroseck,

It is not likely the intermediate shaft plug because that would not have much of an impact on the oil pressure. And because the pressure is low when hot (vs. cold), the oil plug most likely came from somewhere after the inboard t-stat. What about the possiblity of the plug for the oil bypass upgrade (if done) became dislodged. Also, CAPSLOC implies you're yelling at us per the Usual Email Etiquette Manual, Second Edition.

Jim

78 STROSEK · 78 STROSEK's Garage

Racing97
Thanks for the input. The plug in question is the same size as the crank plugs, but I can't find any missing. The crank has seven plugs in the rod journals, and two in the ends of the crank. Still looking!!

studeb · 03-02-2005, 10:50 AM

You say it looks like a dowel pin. How about the No. 8 bearing pin. The one that holds the No. 8 bearing.

78 STROSEK · 78 STROSEK's Garage

The number 8 dowel pin is there. This is a soft plug. Sorry for the confusion. It is close to the size of the dowel pin.

78 STROSEK · 78 STROSEK's Garage

Still looking for missing plug. Afraid to finish motor since I have not found reason for oil problem.

davidppp · 03-23-2005, 02:21 AM

The plugs in the crank are aluminium.

And not all easy to find..

I would look there again, and if in dobt plug all the oilways and just test for leaks..no high pressure needed..

David

78 STROSEK · 78 STROSEK's Garage

David,
Thanks for the input. I plugged the known oil passages and smoke tested the crank. No other holes found.