152 Rear main seal

gglenn

New member
I am restoring a '66 800 with the 152 4-cyl. The engine runs really well, however I do have oil leaking out of the bell housing. I plan to pull the engine out this weekend to clean it and paint both the engine and engine bay. I also want to replace the rear main seal. Everything I know about mechanical "stuff" I have learned during this project. I have a knowledgeable friend who will be helping me, but he has never worked on an IH before. Does anyone have any tips for replacing the seal? Does it require any special tools? I will also be replacing the timing cover gasket and the valve cover gasket.

I also would like to know what the best brand/weight oil to use in it. I read a thread in the oil tech forum, but frankly, it was very technical and I didn't understand much of it. Basically I would like to know, in english, what kind and how much?

If I asked anything stupid, please forgive me! I am a mechanical dummy, but I am learning.:icon_biggrin:
 
Review this thread, it contains two methods for installing a rear main seal set. Disregard the fact that the engine being described is a 345, the process for a 152/196 is identical once the transmission/flywheel/bellhousing is removed:

http://www.forums.IHPartsAmerica.com/gas-engine-tech/1143-sonjamotor-lives.html

You will need to drop the oil pan in order to replace the side seals on the rear main cap, do not scrimp on that, otherwise you will still have an oil leak after the rig is reassembled. So order in a "bottom end" gasket set which contains all gaskets and seals for doing this work and you will have some gaskets left over for future use, that is much less expensive than ordering a seal kit only in the long run. Better yet, order a complete gasket set and you will get the valve cover gasket and the lifter cover gasket.

You will not find the gasket sets in our online store right now, but they are on the shelf. Call the shop at the new phone number, 530.268.0864 and Jeff or michael d. Can fix ya up with what ya need. Ihon also handles the swepco line of lubricants.

Ya must use some form of sealant on the flywheel bolt threads when re-installing, otherwise oil will run right out around all the bolts and appear as a rear seal leak.

I run rotella t in 15w-40 in all my engines now, along with only a wix, or purolator pure one oil filter, a napa gold oil filter is actually a wix product and is suitable also. With a filter change, you are looking at five to five and a half quarts of oil, overfilling slightly on the dipstick tick Mark won't hurt anything at all.
 
Thanks for the info. I had already called in an order for the seals at the local napa store. I only ordered the rear main, oil pan gasket, and timing cover gasket. I didn't even know there was such a thing as "rear main side seals". Is that what I need to tell them to order?

Also, is the rear main a one piece seal? It looked that way to me in the pictures. My buddy was expecting it to be in two pieces. Maybe that is a difference between IH and dodge?

I hope I'm not getting in over my head, but I really want to do this myself. Thanks again for the help.

Gary
 
The side seals should be included with the rear main seal package. The rear main is a one piece seal.

I'm no mechanical genius, but on my 304 I had oil leaking "from my bell housing" but when I removed the cover plate there was no oil on the front (crank side) of my pressure plate so I only replaced the side seals and that took care of the problem. I only mention this because of all the problems I have read about rear mains being somewhat problematic to seal up properly. If it is not actually leaking I wouldn't replace it until it does start.
 
thanks for the info. I had already called in an order for the seals at the local napa store. I only ordered the rear main, oil pan gasket, and timing cover gasket. I didn't even know there was such a thing as "rear main side seals". Is that what I need to tell them to order?

Also, is the rear main a one piece seal? It looked that way to me in the pictures. My buddy was expecting it to be in two pieces. Maybe that is a difference between IH and dodge?

I hope I'm not getting in over my head, but I really want to do this myself. Thanks again for the help.

Gary

The side seals will come with the rear main you already ordered.

The rear main is a single large seal that slips around the rear of the crankshaft.

The napa seals I received before were a "dry" seal. You had to clean everything away (no oil residue) and then the seal was slipped on using a plastic spreader (also included).

If the leading lip of the seal folds under during installation it means you did not make full use of the spreader. Do not try to fix it with the tip of a screwdriver. It will leak worse than before and you'll get to do it again.
 
Thanks for the help. My friend wanted me to ask if someone could tell me the applicable torque specs for putting everything back together.
 
thanks for the help. My friend wanted me to ask if someone could tell me the applicable torque specs for putting everything back together.

Engine assembly fastener torque specs are common amongst all ihc-produced I-4 and sv engines where applicable. Here's a typical from a service manual.
 

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