Engine questions

[Guest 49DeSoto]

Hello,

I have a 1949 Desoto Coupe deluxe. The engine in the car is 25" long. When I understand it right it could be a 251 or a 265?! The engine is equipped with a spitfire head.

I opened the engine because I would like to see the inside to decide further steps.

I started with removing the head and the oil pan, and what I saw looks very good in my opinion. I can still read "std" on top of the pistons.

Than I removed the water pump as well as the water dist. tube (2 days work... )

So I guess, I will buy a new gasket set,a new water dist. tube and some paint and that is it.....maybe!

I already bought a new water pump.

What do you think? What kind of gasket set do i need? What kind of engine do I have?

Thanks for your help

Patrick

[greg g]

Take a look over the generator on the engine block. There should be a number stamped into a flat boss machined there just below the head. A Desoto engine should start with an S, a Chrysler ususlly the host of the Spitfire head would start with a C. If you have an S engine with s Spitfire head, its probably a swap. These heads weren't any different, sptifire was a Chrysler marketing deal. You should be able to get a standard engine overhauld gasket ser from NAPA or other local Auto parts places. It will have more than the stuff you need to bolt your motor back to gether. One note the oil pan gasket is made up of four pieces and the ends that stick out of the end pieces should be left on. the difference between the 251 and 265 was the length of the stroke. 4.5 for the 251, 4.75 for the 265.

[Plymouthy Adams]

Not an expert but my book says for 1949 DeSoto..the engine is a 236.6

1951 was first year for the 250.6 for DeSoto which was by the way largest 6 in the DeSoto

However..pleae note that if your engine number does have an A or B or both A and B you have a "special standard" engine..

A equals .020 larger bore and B equals .010 under standard journals.

As for the Spitfire head..looks like a swap in earlier life...

Now IF the entire engine is changed... say from a Chrysler..pre 52 would be 250 and 52 on could be a 265..the 265 block should start with C52, C60-1, C60-2 or C62 from a 53 model...from then on it was V8

post your block number as found on the engind block boss above the generator...

[Guest 49DeSoto]

The number start with S14 53. Not sure about the following numbers.

I will measure the stroke tomorrow.

I looked at the VPW homepage and they ask about the type of the rear main seal? What do I need?

I will post some pictures of the engine tomorrow!

[Plymouthy Adams]

1950 engine..236.6 cubes 3 7/16 bore 4.250 stroke and 7.00 compression with 112 HP at 3600 RPMw/195 torque at 1600 RPM stand oil pressure @ 45

[greg g]

there are two types of rear seals, the old style impregnated rope type and a newer style neoprene deal.

Here is a site with some helpful DeS info.

http://www.duricy.com/~desoto/desoto_serial_numbers.shtml

[blueskies]

If it were me, and I had the head and pan off, I'd check the bearings, and maybe pull one of the pistons to check the rings...

Here's what all six of them looked like in my 218, with 86,000 miles. Ran just fine, no smoke, and no visible wear on the cylinder walls when I pulled the head.

Pete

[Plymouthy Adams]

Pete..this is very typical of these old engines..good call to always go a bit deeper and inspect..

[Guest 49DeSoto]

Yesterday I looked a little bit deeper in the engine. And you were right. Piston #6 has a broken skirt.

Also 2 Piston rings are broken. The main and rod bearings are already .030 but in good condition.

I also measured the stroke. But now I am completely confused. I measured 12cm (~4,75inch). Any ideas??

So the plan changed:

New Pistons + Rings

New Main and Rod bearings

New Enginge Gasket

Today I tried to take off the pulley. Is there a trick? I have a wide pulley without a dampener.

The pulley has only the center nut and 2 smaller holes????

[Young Ed]

You need the socket to remove that center nut. Then a puller goes in those 2 holes. And don't put the bolts in to the pulley too far or you can damage the front cover.

[greg g]

You need a puller to get the front pulley off. Loosening the large nut can be a challange. If you have the pan off put a chuk of wood between the crank throw and the block to keep the crank from turning. Then you can use an impact wrench, or like I did an old breaker bar and a three pound sledge.

How did yo measure the stroke, or are you talking about the length of the connecting rod???

[Guest 49DeSoto]

I turned the engine till piston #1 was at the lowest position. Then I measured the distance to the top of the block.

It was ease because the head is already off. Is this the correct way to measure the stroke?

The large nut was not the problem, these is already off. I build a puller but no change!!

Maybe my puller is to weak because it started to bend.

What happens with this rectangular pin? Do I have to remove it first?

[greg g]

The stroke measurment is the length that the piston travels, not necessarily the to the top of the block as the piston usually stops short of the top of the block. The key will come out with the pulley usually. Take some penetrating oil and keepit wet for a couple days and if your puller is bending you need another puller. Mine came off hard even with three days of soaking in PB Blaster.

[Tony_Urwin]

As Greg mentioned, a stroke of 4.75" means you have the 265ci flathead.