VCCA Home Forums TECHNICAL - GENERAL Mechanical - Engine, Trans, etc Hydraulic lifters

Hello Chevy lovers, I recently rebuilt my 235 engine, bored 40 over, new rings, bearings etc, etc & upon startup found that i had no oil to the rockers; I ran a 1/4” line from the gauge out let to the rockers & solved the problem; However the engine ran rough so I adjusted the valves to 1/2 turn past o clearance & engine backfires & no power so I had to back off the clearance to o lash. Motor then ran pretty well but not correct & sounds like a diesel . I pulled the lifters & found 4 of them were not pumped up. To the best of my knowledge the block is a 1958 & I installed an 848 head on it. First of all why was I not getting oil to the rockers & is it possible that those 4 lifters lost their prime. Sorry for the long message but trying to explain the whole senario. Do’s anyone have any ideas? Thx for your help. Olgzr

IF THE ENGINE IS A 1958 there will be no oil line in the push rod compartment. 1957 and prior 235 engines had an oil line running from the lower rear corner of the push rod compartment to the top center. On a 1958 engine the lifters and rocker arms are fed oil from the front and rear cam bearings. Oil then passes the lifters and feeds a passage in the center of the block.
That oil zig-zags around a cut-out in the head gasket and goes up to feed the rocker arms.
Did you install a new camshaft? The runing problem sounds as if the cam is for solid lifters.

The 1957 and prior engines got oil from the rear cam bearing to the line I mentioned above.

After giving your problem more thought I came up with this. Because the lifters are not pumping up the piston in the lfiter is bottomed and lifter is acting as a solid lifter, thus the poor idle. A hydralic lifter cam has no clearence ramp asa will cause this problem unless the valve clearence in set very loose.

Hi chevy nutThx for your reply; No I did not install a new cam this time around ( this is the second time I have put this engine together; It was fine the first time around, the only thing I did different this time was install the different head 848)

If there is oil pressure at the 1/8" pipe plug, top cEnter of the block, the problem is the head gasket or something in the head above that point.
The head gaskets for all 235's for 1953-1962 are the same.
An 848 head is a replacement for 1953 and up 235 engines and is basically a 1956 head AND CARRIED ON UP TO 1962..

Well Gentalmen, I put 4 lifters in a can of oil & could not get them to pump all the way up ( still spongy). I then install all of them back in the bores & ran the oil pump with a drill & all the lifters are oiling. There is no oil line inside of the lifter comp. just a hole in ctr of the block 1/4” ? I’m still not getting any oil to the rockers; Is the oil supposed to come thru that hole? I ckd the block no. & it is F0405K & the head is 3836848. ???? HELP. what next? Thx, Richard

Lifters are dufficult to fill with cold oil. Kerosene or Marvel Mystery oil works best. To fill the lifter it must be imersed in oil above the little hole/holes on the side if the lifter and then the center of the top of the lifter pressed up and down.

The engine number ending in K is from a stepvan standup and drive truck. That engine would have had a solid lifter camshaft and solid lifters. It could be converted to hydraulics by just installing a Hyd, lifter cam and Hyd. lifters.

when you ran the oil line from the gauge where did you connect it to the rocker arms to get them to oil?

Did you run/use the engine before it was rebuilt.

Why did you install an 848 head as that engine would have come with an 848 head,

Did the lifters pump-up before the rebuild and you now have the same lifters and camshaft?

Did the rebuilder install new cam bearings?

I need answers to all the above to try tofind the probles.

The front and rear main bearings feed oil to the front and rear cam bearing which inturn feed the oil lifter gallery. The lifters not pumping up lead me to think the main or cam bearings are incorrect or installed incorrectly because the lifters are not getting oil. After the oil passes around the lifters it goes up thru apassage in the block and head to get to the rocker arms.

When the engine was rebuilt the rebuilder installed a new hydraulic cam & new lifters& the engine was fine untill #6 cyl dropped to 55pds& I started blowing head gaskets & found that there was almost no land left in the combustion chamber of the head so I obtained the 84& head. I had no oil to the rockers upon startup so I ran a 1/4” line from the gauge port around to the passenger side of the head. I do have oil to the lifters but none to the head. Yes the rebuilder installed new cam bearings & honed the cylinders & I changed the rod & main bearings and installed new rings.

Just came to mind. On some combinations where earlier heads and/or blocks were mixed a hollow center head bolt was required. On some applications the oil went around the head bolt and on some it went through the hole in the center of the head bolt and came out on the side of the bolt. The hollow head bolt can be indentified by what looks like a shallow screw driver slot on top of the head of the bolt.
The part # of the special bolt was 3764578

The "848" head story.
The head with the 3836848 casting number was used in ptoduction of new vehicles wth a 235 engine from 1956-1962. The casting had a minor change for the larger opening required for the new for 1956 eletric temp. gauge sending unit.
A time a change was made in a casting the casting number changed.
The head also was sold for replacement for 1953-1955 engines after 1956 and came with a reducer for the smaller early style temp. guuge.
From 1956-1962 the compression ratios changed so material was removed from the face of the head. Also in 1958 the rocker arm oil was change by drilling holes. Changes like this had no effect on the casting number as it, the casting, remained the same.
The casting date on top of the head could tell what year the head was from.

The casting number on your block is behind the starter and dificult to see but it would give more information about the origins of the block.

Do a search on Chevrolet hollow head bolt,,,I did it on Bing and came up with better information.

A friend had me work on his engine some time back. He wanted a quieter engine and to not have to adjust the rockers for a long while. He had a shop install hydraulic lifters and the rockers rattled something fierce. I worked on the adjustments for quite awhile. Every time I would get them adjusted and run it around they would be out of adjustment again. Finally I pulled one of the lifters and discovered it was a truck engine that should have a solid lifter and there was no oil passage drilled in the block. I put solid lifters in it and it ran well. He took it back to the shop and had them reinstall the hydraulic lifters. At that point I was done. So to make a long story short. Have you checked the block for that passage? And the next point would be to run the oil pump while that lifter was out of its bore. The oil should just pour out of that bore and if it does not you have a restriction/blockage somewhere. The oil passage is fully pressurized and if enough pressure leaks past the lifters then the ones with the weakest check valve will leak down first, especially at idle . Curious as to what you find. Like Gene said - on some blocks the oil line to the rockers may be tapped into that passage in the lifter gallery. If the rockers are not getting oil this may be a further indicator of having a restriction.

His engine does not have the oil line in the push rod compartment. That indicatesitisa 1959 or later engine. Also 1959 and later engines are all drilled for oiling to the lifters. If solid lifters (or when) used in these blcks the solid lifters are necked down in the center so the oil can pass to the center of the block and up through a passage in the block to the rocker arms.
The engine you are refering to must have been an earlier engine with straight sided lifters and no oil passage,

Is it ok to run the outside oil line from the gauge port around to where the small plug go’s into the top of the head to oil the rockers? If so is a 1/4” line too big?, & is it likely the 4 spongy lifters are bleeding off or possibly not pumped up to begin with? Wouldn’t the lifters pump up while running? Ideas? I’ma gettin frustrated. ????

Yes, it is OK to run the line as described. I think running the engine (DRIVING THE CAR) IS A GOOD IDEA TO SEE IF THE LIFTERS PUMP UP.THE THINNER HOT OIL MAY HELP..

Ok, I will do that; I’ll try to pump up the 4 lifters with mystery oil & see if they stay pumped up; To be continued. (mabye) ????