The Stovebolt Site Forums The Shop Area Engine Shop 292 Chevy strait 6

I have owned this engine and truck for about 15 years, when it first cranks up the oil pressure is normal (30's I believe) but after driving a while and at idle the pressure drops enough that I can not tell it has pressure but I never hear any bearings rattling. While driving the pressure maintains I think about 10 lbs (need to verify that #) I understand this is indicating worn out bearings? Question, is there only one point to connect my oil pressure gauge to (Right lower side of block)? An old mechanic once told me that point measures the lowest pressure but there is another place to measure oil pressure. Anyone know about this?
On the left side of the engine on the head (carb side) what is the what looks like a temperature sensor near the front ? Mine has never been connected to anything. What is that?
Going out to check the cylinder compressions today.
Thanks,

glenn,

As far as I can tell, there is only one (1) port designed to connect your oil pressure gauge/pressure sending unit. See picture attachment below found doing a web search.

On your question about "..what looks like a temperature sensor...", you are correct. It is the original temp sensor for the 292 head. If you look at the snapshot attached below (I took from a picture you posted in the other 292 thread about "vacuum" and "carburetor" issues you have), you can see where your '53 style gauge connection has been plumbed into the thermostat housing elbow instead of using the original 292 head sensor port.

The sensor blocks the port to keep your coolant where it belongs, and you have an alternate temp gauge in use, so not being connected should not be of any concern.

On your low oil pressure description, considering your other thread and descriptions of possible oil blow by and potential significant engine wear, low pressure is most likely another sign of an engine in need of a full rebuild.

Just my 2-cents.

Dan

What weight oil?

Your oil pressure is low enough to be in the danger zone, so an oil pan removal and inspection of the bearings is in the near future. It's better to do it now, rather than wait until a bearing fails and the crankshaft gets damaged. Then the fix goes from a few hours' labor and a few hundred dollars' cost to an engine removal and thousands spent on a major overhaul. Your choice, and doing any other sort of diagnosis won't change the cold hard facts. Oil pressure loss can be from worn connecting rod, main, and camshaft bearings. Rods are easy, mains are not terribly difficult, but cam bearings require a major disassembly down to the bare block. That's major rebuild stuff. Oil pump problems? In 60+ years of rebuilding hundreds of engines, I've seen two oil pump failures- - - -both caused by debris that blocked the relief valve open and dropped the pressure to zero.

Remember the old ad that said "Pay me now or pay me later"? That's your situation, and the "now" needs to be "soon"!
Jerry

Jerry and Dan, and everyone else that I have been bothering but you guys have have sticking power and I appreciate that!
I wish there was better news but I have what I have. To boot I did compression test today, 1- 130, 2- 120, 3-135 4- 130, 5-105, 6- 30. Yes that is a 30!
Sad news for me and the truck. So I'll ponder what to do and how.
I don't have the facilities to tear down and rebuild.I could do it myself otherwise. I turn 70 next month and I'm getting tired of all the bending and crawling on the floor, then I have an MGB that requires and new clutch and I am waiting for warmer weather to get on that one.

Guess I will call around and find mechanics that will and can take care of the truck for me first.

I will get back and let you know where it goes!

Thanks again.
Glenn

If it runs OK and you don't hear any noise, screw a mechanical gauge into the oil pressure port and verify your gauge is working correctly.

Grasping for straws I would assume.
I did verify the bad rings in the 6yh cylinder this morning. Put oil down the spark plug hole, the pressure in that cylinder went up to 90 from 10. I guess it could be a cracked ring but none the less, major work is required.
I don't know if I can locate a short block like with other engines, but I will try.
Glenn

Go to your local combine junkyard and buy a gently used and well maintained 292 out of a combine for $300. Preferably one that had a grain bin fire from leaving corn in there. Here in Indiana they are full of them and you can hear them run before you buy them. JMHO.

That would be interesting! We just determined that the engine is not a 292 but is something else.
I believe I found someone that runs his machine shop and can do the entire job without me having to pull it out or replace it in the next town over.

Glenn

Check under the valve cover on the rockers as well. My 235 was running poorly and had low compression on one cylinder. It turned out a rocker arm was actually broken. One half was sitting on the head surface.

I verified it is a ring issue. I put oil in the cylinder through the plug hole, turned her over and the compression went up to 95 from 10.

Sounds like it needs a rebuild

I decided to do what ever I need to do here, so I found a remarkable shop out in the country near a local town (about 30 miles away). It looks like he runs the shop alone and is deaf. He verified that the parts for the 235 and the 250 are interchangeable? I am assuming my engine is one or the other, None of the numbers on the block verify it for me.
I'd like advice if this price is pretty reasonable?
Pull the engine and replace it. Put in the tank, tear down, bat cleaner, rebuild engine, bore and hone block, service and shave head, replace bearings, Pressure cam gear on camshaft ( I don't know what that means) Check and return rods, R&R pistons on rods,R&R Freeze plugs. Labor $1850.
Parts, New Push Rods, New Pistons and rings, Oil Pump, M.R. Bearing & cam bearing,Gasket set,Timing Kit, Camshaft & Lifter, Freeze plugs, Oil filter and oil. $1535.

He thinks he can start in two weeks. Sounds like he will get on it and finish it pretty quickly. I plan to drive it to him and pick it up afterwards.
Maybe he will let me come over and tear it down and assist putting it back together. I would enjoy doing that, learning and as well as to see it all going back together.
Thinking we will replace the intake with the proper one and put a correct carb on it. He was talking a 4 barrel but I don't know. I don't need a 4 barrel but then I understand that only 2 barrels are in use unless needed. The transmission is a low speed ratio so it wont go fast anyway, 55 is about as much as I do.

I don't think I can buy parts myself any cheaper, plus if he gets the wrong ones its on him.

Glenn

Price is in the ballpark. I will defer the terminology to those engine builders among us. As far as a 4 bbl carb, no way. Find a correct intake and exhaust and
a 1 bbl carburetor. Put it back stock you will be happy you did.

235 & 250 are 2 different animals. You probably mean 230 & 250. Most of those parts are interchangeable.

George

Run- - - -do not walk away from anyone who thinks 235 and 250 parts will interchange. Maybe he meant to say 230 and 250? They use the same block and cylinder head, with different crankshafts and pistons. If the engine is a 250, you can use pistons for a Chevy 307 V8 to get a little more compression. The 250 piston has a dished top and the 307 has all the same dimensions with a flat top.
Jerry

Thank you all for the input. I may have misunderstood what he wrote as far as the engine size, after all he was going by the photos that I have of the engine #'s, which are not good ones. One barrel will do!

Glenn