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756puller    0

I've got a 706 with a282 engine I've had apart a few times for scoring valve guides. I installed a new oil pump and have 35 psi oil pressure. I can get the oil up to the rocker arms but it doesn't seem to have enough volume to run down the rocker arms to the valve guides. Can anyone point me in the right direction? I can't think of anything else to try

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Kevingweq    0

More info please , what has been done to engine ?  how many hours ?  any info you have we need

Just a wild guess , if the major bearing surfaces are worn , ie rod,main, cam, etc etc   the oil pump will not

be able to maintain enough flow /pressure to push oil to the far reaches of its journey . A flow diagram would be nice to have

Valve guides don't really need a flood of lubrication , usually residual splash and oil vapor will suffice , Is it possible

they are getting set up a bit tight ??

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756puller    0

maybe 40 hours on major overhaul. had the head off twice not for gulled valve guides and bent pushrods on #4 cylinder. just installed a new oil pump and oil and filter. just doesnt  seem like i can get the flow of oil to ride on the valley of the rocker arms to get to the valves

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waterloo    0

what is the oil pressure when running? are the passages to the  rocker stands clear. Does the head gasket have the right holes in it to allow oil flow up? Maybe no big enough. I am building a 236 right now. W

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Kevingweq    0

Any signs of aeration in the motor oil ?   Had a cummins once (555)  would not push oil to the top end

or the turbo , ended up being crack in pickup tube flange

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R190    0

Are you using valve guide seals years ago IH had a service bulletin out warning to never use valve guide seals on those engines, do you have plenty of oil dripping out the rocker arm bushings?

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756puller    0

I had the machine shop fix the head for me. I have 38 psi oil pressure at probably 900 RPM. Im sure it has guide seals. I think I do have quite a bit of oil coming out of the rocker shaft for the rocker arms. I just cant get anything to the valves themselves. oil will pool in the rocker arms just wont follow the valleys to the valve guides. I know the rocker rams and supports are assembled right.

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756puller    0

I did have the machine shop install the cam bearings for me. Could it be possible that the bearing that oils the head is off just a bit and not letting full flow of oil go to head?

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waterloo    0

I take it you don't have a IH service manual. I will check mine to see if anything said on lining up oil holes. W

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756puller    0

I do have the ih manual. The way the diagram looks is the pressure gauge is a ways from the bearings. So I'm thinking I'm loosing pressure in the bearings someplace.

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waterloo    0

I looked in my manual today. The front cam bearing has two holes. And must line up with the holes in the block. The only way to find out is pull the cam. That's a major amount of work. W

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756puller    0

That's sorta what has me thinking the holes are off. I basically have a trickle of oil not a gyser.

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waterloo    0

something is not right. I know it is a lot of work but I would pull it apart. I wouldn't say that 38 psi when running is very high ether. Maybe the bearing clearances are too high. Maybe the pump clearances are too. Keep us posted on what you do and find out. W

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Engine service manual calls for oil pressure regulating valve opening pressure: 30-40 psi.

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Owen Aaland    0

The second hole in the front cam bearing is to provide lube to the timing gears. Oil for the rockers comes through the second cam bearing. That bearing has two holes 180° apart. The camshaft has a hole drilled through that journal that lines up with the holes every 1/2 revolution. That gives you one squirt every crankshaft revolution.

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mmi    0

been 30 years  but next to impossible to line up,confirm  those little holes...  ones I installed have galleys to route oil correct

correct interference fit and usually flush (0 protrusion)  clocked for 12 and 6 would set in 11/1-5/7 closer if 2x chalked and helper

do recall note on no umbrella seals  had some stem seals but dont recall engine...

top end does not spray squirt but has good flow at rpm...1/2 qt vs TBSP @ idle 

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756puller    0

Pulled out cam and did confirm the lube holes were right. Started looking at oil pump found oring on suction tube hard as a rock. Wondering if I was loosing enough suction there. Going to pull oil cooler and check the relief valves there also

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R190    0

You already have plenty of oil pressure if you were loosing suction you would not have volume if you would not have enough volume you wont get oil pressure . Have you trashed those valve seals yet? I am finishing up an engine were a so called machine shop put umbrella seals on the stems  guess what the valve guides are shot. If  he was using them because they came with the kit I wonder what he did with all the littler o-rings most after market kits come with. If you have oil dripping from the rocker arms that's usually enough oil because it really flies around at 1900 rpm it bounces off the valve cover and all over.

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waterloo    0

Can also depend on the fit of the valve in the guide. How much clearance did there allow? Maybe they were a little toooo tight. On my 236 build I put umbrella seals on because I am using the guides the where in the head . They are ok but just. W

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MR. IHC    0

I put one of these together once in a pole barn with poor lighting. a new reman block and a reman head. i used it for 1 day bailing hay and had a pushtube fall out, upon getting it back to my shop and tore apart i found i put the head gasket on upside down, it blocks off the supply to the rockers. a hard lesson learned for me! but ill never forget it! just a thought.

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