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New valve stem seals/a little nervous

Maybe I’m paranoid but I’m a little worried to start the car with the oil that’s in the car. The reason is because the new seals are pretty tight on the valve stems and seem that they could prevent oil from getting down to the guides. The car currently has the recommended 10W-30 but was thinking that maybe I should change it to maybe something like 5W-30 before the first start-up - giving the seals time to loosen up and then switch back to the original oil weight after a week or so. What do you guys think?

In case it makes a difference the new seals are Fel Pro viton. Both intake and exhaust.

Why are you worried? They are probably no tighter then when the car was new. Or do you think the car came new with loose fitting seals? Of course it didn’t.


Lighter oil probably won’t hurt, but if installed properly I would think it a non issue.

Alright, I guess I was just a little worried because the new seals aren’t OEM and as far as I can tell made of a different type of rubber. Plus aftermarket parts scare me a little because they’re not always made perfectly to spec but Fel Pro has a good rep so I’m going to take a deep breath and just relax.


Ignore it. Run the car with the manufacturers recommended oil.

You have to consider when the car was first made it had new seals in so just use the recommended oil and be happy.

Fel-Pro would be at the top of my list for seals.

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I had the valve stem seals replaced on the 1971 Maverick I once owned. There were no problems. The shop injected air into the cylinder, removed the valve spring keeper while the valve was being supported by the air compressor, removed the spring, replaced the seal, replaced the valve spring and keeper and then did the next valve. I had been using 10W-40 oil before I had the work done and used 10W- 40 after the new seals were installed. My oil consumption dropped.from a quart every 300 miles to a quart every 1250 miles. As I remember, the work cost between $50 and $60. This was back in 1975.

Isn’t a dab of assembly-lube placed on the valve stems during a head rebuild?

Year of car? Miles? Was this only repair? Or part of a rebuild?
Protege is not collector car. You must like it?

  1. 1.5 litre Z5 engine. 205k miles

I’m not totally crazy about the body style but like the way it drives and the ‘‘looks’’ of the dash, guages and everything else you see while in the driver’s seat. It’s become a hobby of mine keeping up with the maintenance just as much as it is a good reliable source of transportation. Plus there’s some sentimental value since it used to be my mom’s. I plan to keep it until the maintenance is beyond what I’m willing/capable of doing myself. Such as having to rebuild the cylinder block or having to pull the transmission. I’ve also made a game out of seeing how many miles it’ll go on the original engine and tranny. And believe it or not it still has the original alternator in it; still putting out over 14 volts!

It was the only repair as far as the cylinder head is concerned (except for changing out a few valve clearance discs) but I also replaced the water pump, timing belt, all three idler pulleys, both cam shaft seals, the front crank seal and think I solved a tranny fluid leak. But not holding my breath on that one.

The manual said to either do that or just use clean engine oil. I didn’t have the proper grease so I just went ahead and used the oil.

That should be fine.