How much torque on belly pump housing bolts?

Patrick HMD · Aug 9, 2013

I was assuming 90 ft lbs according to the chart. And that's what I was doing. Then when I was doing one of the 7" bolts I heard a loud POP inside, and the bolt got loose. I pulled the bolt out and it was still all intact, nothing missing. I need to pull the housing out to see what's going on.

I added a copper washer next to the lock washer at the top to prevent oil sippage that was occurring. That left me with a little over a 1/4" take up on the bolt. Something that I had overlooked. So I'm thinking maybe the female treads stripped out at the bottom. I'll know for sure when I pull the housing out. I'll probably go get some 7 1/2" long bolts even though the parts book calls for 1/2" x 7".

My question is about the foot poundage. Is 90 ft lbs overdoing it on such a non critical item?

TIA
Patrick
'49M

Nebraska Kirk · Aug 9, 2013

Yes, 90 ft/lbs is overdoing it for that application. Also, don't use a lock washer on the bolts with the copper washer. Just snug them down firm, they won't come loose.

Patrick HMD · Aug 10, 2013

Thanks NK, just as I figured. The problems we create for ourselves sometimes. I'll be pulling it out later today. Hope nothing too serious is happening in there, but that sure was an ugly sounding POP I heard.

Patrick (feeling stupid)
'49M

Nebraska Kirk · Aug 10, 2013

Don't feel too bad, Patrick, I have done similar things that made me wonder "what was I thinking?!!"

D. Slater · Aug 10, 2013

Patrick if you mean the cover with pump that bolts to the rear of the liftall reservoir. The holes are blind so if it was leaking at the top bolt the housing is cracked or its leaking between the housing and gasket to the bolt then out around it. Large bolts the 7/16 ones probably don't need over 45 or 50 foot pounds if that much and the smaller 3/8 bolts maybe 25 to 40.
Don't want to give you bad news but the housing is not very thick at the 2 center top bolts and could have busted. If I remember correct the bolts on the inside are 1/2 inch bolting the pump to plate and were torqued to 85 foot lb.

John G. Hasler · Aug 11, 2013

> Is 90 ft lbs overdoing it on such a non critical
> item?

Not unless the manufacturer has specified a lower torque. Undertorqued bolts come loose. However, you may not have had enough thread engaged. Omit the lockwasher. It doesn"t do anything anyway.

Patrick HMD · Aug 11, 2013

Thanks for all the feedback folks. I finally removed the housing to have a look see. Everything looked in order. No cracks nowhere. The fact that I was engaging half the the thickness of the 1/2" bolt in the female thread was just too much for it to bear. That's the only logical explanation that I can come up with. I have always heard that the take up should be at least the thickness of the bolt itself to be safe. (common sense) Not so in this case, Dumb over sight on my part. I'll be looking for a 1/2" bottom tap to see if I can cut a few more threads inside that blind hole.

Another thing. The bolt was actually 6 7/8" long instead of the 7" as called for. So that just added to the problem. Good lesson learned here--check those store bought bolts. I will discard the lock washers on the 2 long bolts. Hopefully the copper washers with with a bead of silicone will prevent any further oil bleeding out at the top.

Patrick
'49M

Patrick HMD · Aug 12, 2013

The title to this thread should have been titled 'belt pulley housing' instead of 'belly pump housing'. Hope everything makes more sense now. Sorry for the confusion. Now I really feel like an idiot, and a little embarrassed too!

How much torque on belly pump housing bolts?

Patrick HMD

Member

Nebraska Kirk

Well-known Member

Patrick HMD

Member

Nebraska Kirk

Well-known Member

D. Slater

New User

John G. Hasler

Member

Patrick HMD

Member

Patrick HMD

Member

Similar threads