The Stovebolt Site Forums The Shop Area Engine Shop No oil to rocker assembly.

This is in my 55 2nd series 3200. It ran when I bought it, but there was a ticking coming from the valve cover. I just figured the valves needed adjusted. When I pulled the cover, there was definitely some crud in there, but not horrendous. When running, I got a minimal amount of oil coming from the rockers near the center. At this point I figured the rocker shafts were also filled with sludge so I removed them (they were) and cleaned them. They hadn't been getting any oil to the front or back for a long time as the shafts were badly worn.I planned on replacing the assembly once I was positive there was oil getting to the top. I also plugged all of the pushrod holes and cleaned the top of the head out. At this time I put everything back together and fired it but was now getting no oil to the top, so I removed the oil pan. The pick up screen was completely blocked so it was removed and cleaned before being re-installed. There was a very minimal amount of sludge in the pan. After being put back together I fired the motor, but was still getting no oil to the rocker assembly. Now I removed the rocker assembly again. I also removed the distributor so I could insert my gutted distributor to just operate the oil pump with a drill. With the rocker assembly removed and a drill hooked up I was hoping oil would come out of the hole where the feed tube is. The pump has resistance and there is pressure getting to at least where the gauge hooks up, but absolutely nothing to the head! I am assuming that the passage that goes up the right side of the block is plugged, so is there any suggestions as to clean it out? I know the motor is old and most likely pretty worn out, I was just hoping to get a couple of miles out of it before a motor swap at some point later on (I need to hit the lottery first). I am also confused about the casting numbers on my motor. I thought the trucks were supposed to have solid lifters. I'm pretty darn sure mine are hydraulic. The block number is 3764476. And the head number is 3836848. I have found conflicting info saying that it is a '56 and also that it is a '58- '62. I figured that it may be a '56 motor being a second series. If memory serves me correct, I don't remember seeing the oil line that runs behind the bump in the side cover. I thought my motor should have it. I could be mistaken though as have been into a '54 motor just prior to this.I think I'm starting to ramble on here, sorry. I'll leave it at this for right now.

3764476 was used 1956-1962 - car & truck block
3836848 was used 1956-1962 - car & truck head

Post the engine serial number that is pressed into the block to the rear of the distributor. That should ID car/truck.

Thanks Tim! I'm still pretty darn sure I have hydraulic lifters though. They have the thin wire clip that holds the seat in at the top. That's what is confusing me.

The car blocks 56-62 would have had hydraulic lifters.

The truck blocks all came with mechanical lifters, but only the 1958-62 truck blocks were set-up from the factory to be able to use hydraulic lifters.

The engine serial number will tell you if the block is a car or truck block.

If you want to know the year of the head/block, you need to post the block and head date casting codes.

The date code for both the block and head are G 16 9

Would I be correct in saying that translates to July 16 1959?

Engine Serial # F717A

Good decoding, Matt

F717A
F = Flint, MI
7 = July
17 = 17th
A = 235 car engine, with 3-speed or overdrive

This engine would have come from the factory with hydraulic lifters.

http://www.1954advance-design.com/chev-specs/1959-Chevrolet-c-ser.pdf
http://www.1954advance-design.com/chev-specs/1959-t-ser.pdf

Matt, I would recommend pulling the center outer(passenger side) head bolt and run the drill again and see if you get oil there.

I will try that tomorrow Dave. Thank you very much! I'll let you know what happens. I'm still hopeful that I can figure things out here.

I guarantee we can figure this out!

I like the idea of getting every last mile out of these work horses. Too may people give up on them too soon.
Carl

Yep, that was it!! Pulled that bolt, hit the drill, and out came oil! I guess my next step is to locate one of those special bolts. And while I am at it, a useable rocker assembly for a '59 235. I know that this problem being what it is and being this way for an unknown period of time and miles has put my motor through hell, but my short term goal is to get it running as good as it can so I can use it for a few of these summer months at least. It might be wishful thinking, but I'm gonna try.

After reading the article here, I guess I might need to get a rocker assembly of the right year and no special bolt. I'm not really sure. I'm trying to figure out what rocker assembly I have currently.

http://chev235guy.blogspot.com/2012/09/drilled-head-bolt-drilled-head-bolt-is.html

Did you read my Blog post about rocker oiling? It will tell you which rockers you should have.
As far as oiling, you may be sludged up in the head gasket passage. A drilled head bolt would bypass this problem area.
It is not hard to drill your own bolt if necessary.

Drilling the bolt really isn't necessary- - - -just put a deep groove with a 3-cornered file or a Dremel tool cutoff wheel in the threads from top to bottom. It doesn't hurt the strength of the thread and it's simpler than drilling.
Jerry

Ok, I checked my assembly. I have the rockers with the offset groove and the tube on my rocker connector is the 3rd of the 3 styles pictured. I need a replacement rocker assembly (at least I believe I do) because my shafts are badly grooved at the far front and rear ends. Am I correct that if I find a 59-62 rocker assembly that I shouldn't need the drilled bolt...but I probably want to use one due to the fact that my head gasket is most likely sludged up?

I would say you have it! Except the 1953-58 rockers would work fine. Really the only down side of using the earlier rockers I have seen is keeping the valve cover gasket from leaking due to the extra oil.

Awesome, thank you all! Gonna keep a look out for a rocker assembly and drilled bolt. I'll just drill mine out or put a groove if I have to. Dave, do you have the spec for the diameter bit to use if I do it myself, and how far up to take it?. If I cant find a complete assembly, I may see if I can just replace the shafts. I know I can get new ones for about 40 a piece. I"ll put a want ad up on here. It might be a while before I can get to it, but I'll update when I make something happen. If anyone has either of those things, please send me a message. Thanks!

I believe it's a 1/16" hole through the center of the bolt to a point just above the threads, and a hole drilled from one side to intersect it.
Jerry

If you have not seen my post on my Blog ,I show pictures and hole size.
This drilled head bolt and 1/16" hole size is really designed for using the centered groove rockers. It would not hurt to have the hole size a little bigger when using offset groove rockers.

Well, I got a decent used rocker assembly ('55)and a drilled head bolt from a couple of folks on this board. I was fairly confident that this would take care of my oil to the rocker issue. Unfortunately it did not. With that head bolt completely removed and my oil primer pushing oil, it comes out of that head bolt hole and also where the tube to the rocker shafts goes. So I put the drilled head bolt in, and yes I checked that it wasn't blocked, and nothing. No oil at all comes out. So I figured I would try with the original bolt for the hell of it and got the exact same thing, nothing. Pulled the bolt out and tried again, I get oil flowing through again. Whether or not it has anything to do with this issue, I am also getting a bunch of oil out of the back of the motor. I can't tell if it is the rear main seal or the oil pan gasket, but it is coming out when I spin the oil pump. I installed a new oil pan gasket and there is always a possibility that it may have slipped when I installed it I suppose. I'm not sure what to check for now. Am I supposed to replace the head gasket when using the earlier rockers on the later 235? Any other suggestions you guys might have?

With the drilled head bolt removed, I would remove the 1/8" pipe plug on the passenger side in the center of the head. I would then run a rod through this passage, which goes over to the bottom of the port the rocker connector fits into. Or blow backwards with air in the port in the head where the rocker connecter attaches. It sounds like this could be plugged.

I thought I had already done that, but I think I may be losing it, so I did it again. I poked around in that port and also down past where the head bolt goes. I didn't really feel any type of blockage or resistance in either, but it worked! First I plugged the head bolt hole with my finger and it pumped oil through where the connector goes, so I started the head bolt and tried it and it pumped oil, then I torqued the head bolt and it was still working so I installed the rocker assembly. I primed it and I got oil to come out of the tops of the rockers. One problem down and many more to move on to. Thank you for your suggestions, they helped a ton!!

Good to hear!

I want to put this thread to rest, but I am still having an issue getting oil up top when the motor is running. It runs, but I get no oil out of the rockers like I did when using the primer. I get oil pressure when it is running, but no oil to the top. I just cant figure out why I am getting pressure when using an old distributor as a primer, but as soon as I put the distributor in and start it I get nothing. I thought that maybe the distributor isn't seated properly, but it seems like it is. I would think that If I am getting pressure it should be seated all the way, right? Any other suggestions?

Did you try bumping up the RPM while watching for oil?

I did. I was under the hood while it was running and thought that might do it, but unfortunately it didn't make a difference. I'm definitely at a loss here.

Matt,
I put a different distributor in my 261 and cranked it on the dolly. I had completely rebuilt the engine for my '59 truck.
I had just poured the new oil into the top of the engine and then cranked it. It ran a while and I observed it but after a bit it squealed and I immediately shut it down. I didn't see that it wasn't oiling from the oil poured in earlier and I had no reason to suspect "no oil supply".
I wasn't fast enough, My new bearings were toast!
The problem, though I never dreamed it could happen, was that the distributor tang didn't reach the frapping oil pump slot!
I measured, re-measured, scratched my head, measured again, made an adjustment to the vacuum advance (It can be adjusted up and down the distributor shaft) and I'm now getting oil.
Unfortunately, that lesson cost me a brand new do-over rebuild and my excitement over getting my restored truck back on the road was a disappointing set-back.
I'm not saying this is your problem, but the problem sure sounds familiar to me.
Best of luck,
Jerry

Thanks Jerry! The next chance I get to work on it I will definitely loosen that clamp on the vacuum advance to see if I can get it to drop any further down. I believe it is engaging, but I'm willing to try anything at this point!
Thanks,
Matt

Matt, check your PM.

Matt, the issue of the oil coming out the back may be a guide to your problem. The rear cam bearing has a freeze type plug preventing oil pressure from leaking out. To check the bellhousing will have to be removed.

Jerry has a good point because that is a real issue that I can attest to. There is supposed to be a rubber O-ring on the top groove of the distributor shaft. Problem is, it makes it harder to get the distributor down far enough. Not sure why that O-ring is there. But, very important that you have no more than 3/8" between the top of the distributor shaft and the top of the vac advance shoulder.

It is not enough to watch the rotor go round and round. Check oil pressure the first thing you do. I wonder if it wouldnt just be a good idea to remove the O-ring? Today while working on the process of readying for the initial break-in run, I was able to get oil to the rockers with the drill, no problem. First attempt at rotating with the starter (dizzy in), nothing. It wasnt down far enough!

Deve,

On what engine and what year: "There is supposed to be a rubber O-ring on the top groove of the distributor shaft." ?

I know you are being tongue in cheek Tim.
I will answer your question for Deve.
Although a lot of rebuilt distributors come with an O-ring in the top groove there is not suppose to be anything. That Groove is an air gap to prevent oil from wicking up between the dist housing and the block.
With an O-ring in that groove the distributor will have a hard time rotating with the vacuum advance, IE: not at all.

Makes it hard to drop in the distributor also.
This one from napa came with an oring, once I removed it it dropped right in.

Was giving me a fit

Good. Anecdotal evidence would be that they all came with them. I have 7 distributors and 4 of them had one. Yet every engine I have built over the years didn't have. Oh well, good to know. Looks like I have some more editing to do. Thanks everyone! Hope this helps the OP.

Now how friggin frustrating is that. A brand new dist. from Napa has an o ring when it shouldn't. How can that even be? Did some year models use the same dist. but needed the o'ring, and some didn't. I trust you guys, but how can we be sure (I'm now heading to my shop manual) that we don't need one.

Allen,

As Dave posted:

"Although a lot of rebuilt distributors come with an O-ring in the top groove there is not suppose to be anything. That Groove is an air gap to prevent oil from wicking up between the dist housing and the block.

With an O-ring in that groove the distributor will have a hard time rotating with the vacuum advance, IE: not at all.

I have at least eight 235/261 distributors and none have an o-ring (as they should not). All were collected more than 15 years ago.

Thanks Tim & Gus...another great piece of information from Bolters. Also more support that when you are taking an engine apart and rebuilding, take lot of pictures.