New project I have some ???s

[M5-]

I guess this will be an introduction as well as a request for some help. I picked up this 65 stepper a few months ago as I've had my eye on it for several years and the guy finally put it up for sale so I bought it. All and all the truck is pretty solid as it has spent its entire life in Montana. My questions are currently related to the engine. I'll tell you what I have and maybe you guys might be able to figure it out.

The original build sheet is in the seat and it lists the engine code as "UH" which from my research means the truck came with a 292. On the build sheet there is a line entry "4L25AD Optional 170 HP engine" as well as one for the 4 speed which it has. I can't find any reference to a 170 HP engine any place. To further complicate the issue the casting number on the block is 38877178 which can be a Buick/Olds/Chev/Pont/GMC 230-250 from 62-78. Clearly the engine is not a 292 and to verify that I checked the block stamping which is F0414TF which should mean its a 250 built on the 14th day of April in Flint. The date code on the block is D 12 5 which should mean the block was cast on the 12th day of April either 1965 or 1975. The last 6 digits of my VIN are 143503 which I would think means the truck was built in late 65 almost 66. GM switched to the 250 in 66 could they have installed a 170 HP 250 back in 65?. If my engine was a 250 from 1975 it should have the integral head/intake manifold. So I thought OK I'll just look up the head casting number but all I can find on the head is 4888F7. Where should I be looking for the head casting number?

Thats probably enough questions at once. If anybody can help me out that would be fantastic. Here are some pics.


Thx
Paul

[M5-]

Couple more pics

M5

[raycow]

Unless someone did a lot of parts swapping, that is a believeable looking 1965 engine. It has open PCV and a Rochester model B carb. Naturally, I would very much like to see a pic of the passenger side below the pushrod cover. Actually, I just need to see a pic that shows the fuel pump and the mount.

Assuming for the moment that it's not a 292, the most likely explanation is that a PO swapped it in because he needed an engine and this 230 was available. No production 250s were built as early as April 1965, and no production 250 from this time period was rated at 170 hp.

I believe the build sheet, assuming you matched it to the truck's VIN. If you know that code UH means a 292, then 170 hp is about right for the 292 in those days. I am still looking for a brochure from around 65 that lists hp ratings, and I will post here as soon as I find one.

Lastly, if you can't find a casting number anywhere on the outside of the head, I think the next best place to look would be under the valve cover. If you are wanting the casting number to find out if it is an integral head, it isn't.

A more interesting mystery (at least to me) is why the valve cover, pushrod cover, and intake manifold are yellow and the block and head are green.

Ray

[raycow]

Here ya go - 170 hp from 1964.

http://www.oldcarbrochures.com/main.php?g2_itemId=47905

Ray

[M5-]

Thanks for the help, its starting to maybe make some sense. Could it be the original 292 top end on a 1975 250 bottom end maybe?

I wish I was at home right now and I would post some more pics but I'm at work and I'm leaving town till Wednesday. As far as the green and yellow thing goes I'm thinking farmer with John Deere stuff. Somebody has been into the engine at some point for sure as there is orange silicon all over the place. I'm not too familiar with these engines but to me the rocker plates on the side look like 230/250 size not the taller 292 ones. I will post a pic when I get a chance. The stamping code next to the distibutor also points to 250 being that it ends with code TH or at least thats what I've read in a few places including the LMC catalog which I wouldn't take to the bank. The casting number on the block decodes to 250 as well from what I have read.I found the page below on here and that's where I got the UH thing from to match to the build sheet. I'm sure the build sheet is original but I haven't tried to get it out as it looks like it's about as delicate as an ancient scroll from an Indiana Jones movie, I'm afraid it'll turn to dust.

Maybe when I get home I'll pull the rocker cover and see what it has for a head.

Thanks again
Paul

[M5-]

Here's a few more pics to help with the ID. I can get whatever pics will help.

Thx Paul

[M5-]

OK

I pulled the rocker cover and the head casting number is 3864886 which codes out to a 230 head. The Date code is D 13 5 which is a reasonable match to the block date code. Again my confusion is with the TF (Supposed to be a 250) Suffix code on the block plate and the UH code on the build sheet meaning 292.

Thx Paul

[raycow]

Originally Posted by M5-

Here's a few more pics to help with the ID. I can get whatever pics will help.

From your pics, the engine is either a 230 or 250, and the casting date nails it as a 230. A 292 would have the fuel pump located to the rear of the mount instead of in front of it. As for the TF suffix, GM often used the same code for multiple years, which is why you sometimes need the casting date in order to insure positive identification.

On the evidence of your build sheet, it is almost a certainty that the truck had a 292 as built. That engine probably failed at some point and the owner decided it was more expedient or cost-effective to replace it instead of doing a repair or rebuild.

The one aspect that still has me puzzled is the yellow external parts. While the valve cover and manifold could have been transferred from the 292, the pushrod covers would have been too tall to fit a 230. Do you think the truck might have had three engines during its lifetime?

Ray

[ljackson]

Here is some good info on engine ID. http://67-72chevytrucks.com/vboard/s...d.php?t=412949

[M5-]

From looking at your link everything points to a 65 230 except the TF code on the suffix plate. Are there any decent sources for decoding the suffix plate with a bit more accuracy other than the LMC catalog?

Thx

[M5-]

After a quick check my starter has 3 bolts if that helps anybody.

Thx Paul

[Martin64]

Except for the John Deere color scheme, that motor is pretty much identical to the 230 I currently have in my truck.

[DPowers]

If only they could talk....
Nice looking truck by the way as well.