Truck block engine id help

[ja82]

Just got this truck block has a number on the rear of block, 3979818 , the number on the front is partially erased all i can see are the last letters look like 22TJX,Help please want to know what and where this block is from to buy the parts for it, thanks any help would be appreciated, thanks

 

[ChevyHiPro]

Hello ja82 and welcome to the forum!!

From the partial Engine Assembly Code you have, 22TJX, the TJX is the part of the number that will give us the most information.
This is the Engine Suffix Code, it cross references as;
TJX 1972 307 cid fwrd cab 135 HP 2 bolt C-20 & 30
TJX 1973 350 cid conv.cab 155 HP 4 bolt C-10 to 3500
TJX 1978 350 cid conv.cab L LS9 165 HP 4 bolt C-10 & 1500

Nearly all T, Tx and Txx Engine Suffix Codes are for trucks, buses and some commercial vehicles, large trucks, taxis, police cars, etc.
These Engine Suffix Codes are reused by the engine and vehicle assembly plants.

To narrow it down to a 350 cid or 307 cid, look on the rear portion of the block, in the area between the passenger head surface and the transmission mounting flange, you will find a cast mark (raised letters/numbers) 5.0 L, or 5.7 L.
5.0 L = 307 cid, 5.7 L = 350 cid.

I have had a little trouble running down the Engine Casting Number you posted, 3979818.
I don't have my reference books with me at the moment.
But, the Engine Casting Number will give us a larger range of years this block was cast, not really much help.

Regards buying parts for this block to rebuild it or whatever, all the internal parts will fit, once you've determined if it's a 350 or 307. All these hydraulic cam, small blocks are the same, without respect to bore dimensions and stroke.

If you need any additional information about your block/engine, just post the questions.
There are some knowledgeable folks here abouts!!

Don'tt be a stranger to the forum, stop by from time to time and fill us in on what your doing with your engine build!

 

[ja82]

Been having some trouble getting around the site, been wanting to keep you posted. Well got it all back in its running, but has this squeal that just don't stop, put a high performance cam, new chain, lifters, rods, water pump, high vol oil pump, rollers, even got a different power steering pump, now the squeal stops and comes back don't know what to do any ideas.

 

[ChevyHiPro]

Please pardon my delay in response, life has gotten busy recently!

The squeal may or may not be a problem, but in reality, shouldn't be there!
There are several places that I can think of off the top of my head; the new timing chain maybe dragging on the block or the timing cover. That'll mean removing some stuff to get the timing cover off.
You may want to stop by Harbor Freight Tools and pick up a Mechanics Stethoscope, their like under $5.
Use it to listen directly on the engine with it idling, say on the timing cover, then on the block just beside the timing cover on both sides, above and below, etc.
The other thing could be a rocker arm or lifter.
The best way I can think of to check this out is to, remove the valve covers, one at a time, crank the engine, make sure all the rockers have oil pumping up out of them.
Oh, wait, you got a roller cam, well, same deal, make sure the rockers are getting lubed.

We have an engine building expert on the forum, Ed Hurst, I'm going to P.M. him and ask him to check in on this thread and see if he can offer you any more help!

Post again how it's going, we're interested in keeping up with how things are going with your build!

 

[hurst01]

ja82,

Howdy, but I am not an expert. I have always heard that an Ex is a has-been and a Spert is a drip under pressure. OK, you can quit laughing at my joke now.
Reading your post, the first thing that comes to mind when you say "squeal" is a vacuum leak. It can leave a high pitched, piercing squeal. Something like a chain rubbing would be a grinding noise. I have seen instances where the engine clearances is too tight that might cause this, but I wouldn't start reading too much into this yet.

What kind of oil pressure are you showing? How long does it last when it comes? Any specific RPM? Have you checked the vacuum on the engine? How do you have your timing set? Probably the first thing I would do is to get something like Gumout Carb cleaner in a spray can. It is flammable and will not leave a residue on your engine. It WILL remove some fresh paints though, so be careful. Spray it around the carburetor and intake system, vacuum hoses, and along the edge of the intake/head mounting surface and see if you hear a difference.

I have had leaks like this before. Also, remove the air cleaner to see if it might be coming in through the top of the carburetor. Let me know either way how it turns out.

 

[ja82]

Thanks guys for your help, rounded off the squeal to the fan belt thought it was originally the steering pump and changed it out with everything else, but it has a double groove pulley and when there us a belt on the front groove it squeals, don't know why but goes away after a while when driving down the road, now my problem is emissions can't pass getting real high hc readings its up to like 864 ppm, got the co level down with adjusting the carb but with doing that the hydrocarbons level went up going to take to a mechanic shop tomorrow , hopefully he gets it to pass, also put a high vol. oil pump in there but sometimes the oil pressure goes down to zero what could that be, but after all it runs pretty good, this is my first minor build i love this truck any way to post pics.Thanks for your help totally appreciate it.

 

[hurst01]

I guess i should have asked what area the squeal the area was coming from. If you replaced the oil pump with a high volumn and it still drops to zero, I expect you have a bit of a problem.
(1) It could be excessive bearing clearance in the lower end.
(2) Possible a cam bearing that is rotated blocking off an oil port.

Did you go through the bottom end when you had the engine apart? What is kind of pressure do you have cruising down the road? When does it drop back to zero?

As far as the pictures, when you go to post, use "full editor". At the bottom where the signature goes you will see two tabs, one gives posting "options", the other says "Upload Attachment". By using the latter, you can post your pictures. Looking forward to seeing them.

 

[ja82]

well still having trouble using the site here, but we were talking about the oil pressure remember in the 69 Chevy truck.well when driving the pressure is there but when stop at light it something the pressure goes to 0 like no pressure then when i go it goes up again, but can hear ticking like no oil, now started driving it but after a while starts spitting oil from the little breather on the valve cover thinking if getting taller covers will it affect anything.thanks for your help again

 

[ja82]

Oh and didn't really go through the bottom end like you asked was kind of excited to get it going, but didn't really think was much wrong with it guy had said that they parked it because the.y cracked a head but other wise was an every day driver.hope i don't have to do it all over, but it runs great lots of power

 

[hurst01]

If the oil pressure is dropping down to zero when stopped, you probably have a bearing clearance issue. What is the pressure while driving? I recently helped out with an oil pump change on an engine that was doing just that same thing. He was holding about 40 PSI while driving. When stopped it would bottom out to zero and the lifters would begin clattering really bad.
He put Lucas oil treatment in the engine and the clattering stopped. We changed the pump and the pressure went to 60 PSI while driving but still drops to zero when he stops. He is driving it as needed like it is but I would be afraid to trust it on a long trip.
I had another one with very similar issues last year. Turned out to be a cam bearing that had spun and was blocking one of the passages. BUT, because it had spun, it had excessive clearance and was knocking all the time. I rebuilt the engine and now it holds way too much pressure. 100 PSI at 5000 RPM.

 

[ja82]

jeez wish you didn't live so far so i can drive it to you. hard to find someone knowledgeable willing to share their knowledge but yea i get about 50 psi driving slowly decreasing pressure the longer i drive.