Perkins assembly

OliverNate · Jul 20, 2019

Just about got everything I need to put my Perkins 4.165 back together. This engine has been nothing short of a nightmare to work on. Seems any parts are hard to find. I found a water pump that is close enough to being correct just need to be modified to fully fit. My head that came off engine was welded once already so it was junk. The place it got sent to somehow had one sitting there (extremely lucky) just missing the combustion cups.

I managed to find torque specs and valve clearance. Looked it up under 4.154 (same engine family). Head bolt torque is 85 ft-lbs and valve lash is .012 cold. Just can't seem to find if the head bolts are torque to yield? I'm assuming not because few overhaul kits I found did not include head bolts. Also I know some people like to use their favorite brand of sealer on head gaskets. So I'm wonder if I should use a sealer on this one or not? It has silicone impregnated into the gasket around the coolant and oil holes.

Destroked 450 · Jul 20, 2019

Vary few of the older engines used torque to yield bolts, not sure if Perkins ever did.
Those head gaskets are designed to go on without addition sealer, but I've experienced a few coolant and oil leaks from some engines so I now give any head gasket a coat of copper spray before installing it for added insurance.

jimg.allentown · Jul 20, 2019

It has been my experience that gaskets that have sealer built into them will seal better and work better if you put them on dry. Any unevenness in extra sealer that is applied to the gasket could actually cause leakage. If the deck and head are truly flat, you should not have a problem. If things are not flat, even extra sealer will probably not hold.

Proper torque is important. Too much can distort and warp the block and head castings. Too little will result in insufficient clamping force. Torque pattern is not critical normally. Start in the middle and work your way out in increasingly large circles.

Head bolts on engines that age should not be torque to yield. That technology was probably not even invented when that engine was built. My guess would be that some kits are coming with head bolts because the original bolts are probably corroded and of inferior material. After all, they are how old?? As much as 60 or 70 years old? Maybe older?

SkipperII · Jul 20, 2019

On older engines, I look to see if the head bolts show signs of stretch(the upper threads will be slightly further apart than those that have been engaged in the head). If they show signs of stretch, I replace them with CAT grade 8 bolts.

jtwat · Jul 20, 2019

If both surfaces are flat and clean, no sealer is used with that type of gasket.

Perkins assembly

OliverNate

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Destroked 450

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jimg.allentown

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SkipperII

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jtwat

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