The Stovebolt Site Forums The Shop Area Engine Shop Oil not getting to rockers on a 235!?

Well from one problem to the next!

I have a 1960 C10 with an original 235 6 banger. I was going to adjust the valves when I noticed the rockers were not getting enough oil.

I pulled the little plug that is on the side in the middle of the head right below the valve cover level. I tried cranking the engine with the coil plug removed to find no oil coming from the plug. Then I decided to re- connect the coil and start the engine only to find a trace of oil coming out of the hole.

Shouldn't there be more oil coming out?

How does the oil travel up to this hole and/or rockers? I noticed there is a head bolt in the same spot on the inside of the value cover. Is this where the oil travels up?

FYI.. The engine has 110,000 miles and yes, it shows. If I can get the oil up to the rockers, I plan to clean out the entire rocker bar.

Thanks.. Russ

Here is some information 1959-60 Shop Manual supplement. These engines use a different approach for getting oil to the rocker arms than was used on the earlier engines , such as described in the 1955 shop manual.

Hope that this helps.

Hoyt

Russ,

Yes, you should have oil coming to the rocker arms and from the passage that you unplugged. The shop manual page Hoyt provided shows the oiling circuit for your engine. I think the head bolt you mentioned should have a relief just below the bolt head, to allow oil to flow around the bolt and to the rocker arms, but memory is foggy on that point. Since you don't have oil coming through the passage from below, it sounds like you have a blockage in the oil galley, in either the head or the block- that was not uncommon in those models as they got miles on them. You might try filling the oil passage with penetrating oil or some engine cleaner solvent to see if you can loosen the blockage. Some say diesel fuel works for that purpose, but I haven't tried it, other than for penetrating oil. It seems to work for that. You could also try probing the oil passage with heavy, stranded wire (12 or 14 AWG) as much as you can, to see if you can open up the galley. The stranded wire of that size is stiff enough to break soft blockages, but still flexible enough to bend if it needs to.

The lack of oil to the rocker arms could also be the result of internal leakage and low oil pressure. If you have reasonably good oil pressure at idle, that is not so likely, so don't get involved with that just yet.

Harvester

another thing to do is to run a line from the oil presher gadge hole on the low left side run it a round the back of the block and hook it into the pipe plug hole in the middle of the head.

we did that on my 57 when the block becale pluged and no oil was getting to the rockers.

The answer according to my limited experience is that it depends on the head.

Some engines will deliver the oil directly from the block to the head via a cast gallery then up into the rockers. This gallery is in the middle of the head right where that little plug you mention is.

If this is the case, the yes you should get oil out of that small plug.

The second method is as described already, by plumbing a line directly to that plug on the side of the head. If the head doesn't have a cast oil gallery coinciding with the block.

Third way that I know is to actually have a copper pipe run inside the engine behind the push rod cover. At the back of the block there is a 1/4 in NPT oil supply that cab be plumbed to the head via a copper pipe.

I have personally seen each of these configurations on different engines that I have played with in the past.

Elias

This may be hard to believe but I cut a groove in the center starboard head bolt. This allows oil to get up past the blockage and avoids having to do any plumbling. It was going to be a temporary fix but it worked so well I just left it. I have 25,000 miles on her now.

Thanks everyone...

I plan to check the oil pressure at the sensor first. Need to be sure she is making enough pressure.

Any idea what pressure she should be pushing?

Also, I heard the idea of running a line from the sensor up to that inlet might take pressure away from the bottom half of the engine. Any truth in this?

Thanks for the other idea's! Keep them coming. I just hope there is life left in the engine. I really can't afford to do any major work on her in these times :-(

I've heard that several people have seen a 5 psig drop in overall oil pressure after adding a filter. I'm not sure the same would happen with just some tubing.

I have a '54 325 that has oiling problems, mainly from dirt. I want to take the valve gear off and hose it down at the car wash, then replace the rocker shafts and put it back together. I'm hoping to get away without readjusting the valves.

My question is: due to the dirt I can't tell how the oil line tubing connects to the rockers and block. Do I only need to take it apart at the fitting behind the rocker cover?

I have heard a few people (outside of this forum) say to use Engine Flush. My response is: Doesn't the oil have to first be getting up to the rockers for it to do any (if at all) good?

Also, wouldn't that clog up the oil pump?

To make it more interesting, I had a '51 1.5 ton with a 1954 235 in it, and it had the oil filter option.
I took the oil pan off and there was at least a quarter pound of sand sludge in the bottom of the pan.
I think that the engine flush idea might eventually eat through the oil line blockage, but would like to hear from someone who has done a full purge. I'm not sure whether the sludge would stay in the bottom of the pan or clog the pump inlet.

“Danger, Will Robinson!”

If engine "purge" of any type is used, consider first cleaning the pan (to get the gunk the properly drops out of non-detergent oil and/or which accumulates over time).

Also, use a new filter. After purging, change the filter, and clean the pan again. I'd repeat the filter change and pan cleaning at least once with clean oil, after running the engine.

Any idea how hard it is to drop the Oil Pan? Does the pump get in the way?

Removing the oil pan is simpler than described in item 20 of this page in a Shop Manual (you really do not have to turn the engine over, on a stand or, especially, under the truck). The gasket might cause the pan to stick to the block, but light taps on the side of the p[an usually cause it to drop off.

The oil pump does not usually get in the way, if you are able to drop the pan straight down enough to clear the pump - move the pan to the front or to the rear (just look around below the pan and strategize in which direction you want to remove it).

Oh yes, be sure to empty the oil from the pan before removing the pan.

Just an update: It does seem that the one engine bolt does have a channel in it for the oil to flow through.

I took out the bolt, cleaned the channel with pipe cleaners and re-installed the bolt. I also blew out the rocker arm assembly to find only 2 rockers were plugged.

Anyway, I have to try the Marvel Mystery Oil trick as I used that to clean out the channel.

BTW: I have 35 to 40 lbs of oil pressure so at least that is working!

Hope for the best.

Special Head-Bolt with hole through it.

Just an update:

The engine is back to the usual noises it makes with the solid lifters. I am running thinner oil with Marvel Mystery Oil in it.

I fear she is still not getting enough oil on top. I forgot to mention that even after all the cleaning mentioned above; it still does not seem to get enough oil up top.

When I had the head bolt out, I disconnected the coil and cranked the engine over. I expected to see a lot of oil coming up the bolt hole but found only a little. I also would expect blue smoke out of the exhaust with the thinner oil (As it has in the past) but no blue smoke when going down the road.

It just might be time to get the engine rebuilt. She has 110,000 miles on an engine without an oil filter running on Non-Detergent oil for most of her life.

take the side cover off, (big cover on side of block behind the dist.)look all the way to the rear you may see a small copper tube, it comes from the rear cam bearing and feeds the rocker arm shaft through a passage where the bolt you are refering to is. Take the copper pipe off and blow it out with compressed air, probably plugged up. I know some of the later engines don't have this as the passage was changed, but my 59 261 is not supposed to have it and did and it was plugged up, I cleaned it and it worked, I removed it and capped the passage at bothe ends and it worked even better. The moral of the story, you don't know what was done by who over the years so take time to check it all for possibilities. Also look in a shop manual, it will have a schematic of the oil passages.