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PyrBliss
08-02-2017, 06:39 AM
Ok. So after driving my new to me MM for 2,167 miles, I have noticed that it was down almost 2 quarts of oil. Confirmed blue smoke on start up as well. After searching it seams most likely culprit is the valve guides or stem seals.

My logic tells me that to solve the problem correctly, I had better be ready to get the heads rebuilt. I was thinking of pulling them off this winter (want to forged the bottom end anyway so they are already coming off) and send them off to MHS for a complete overhaul. I figured I would use MHS since I planned on buying some Diamond pistons and Manley rods from them anyway.

Going forward, what exactly causes the valve guides to wear? Is it excessive heat? Once I get the heads redone, I would like to avoid or minimize this issue in the future. Thanks guys.
Zack
08-02-2017, 08:46 AM
Just replace the seals. It's difficult but can be done in the car
PyrBliss
08-02-2017, 09:15 AM
Just replace the seals. It's difficult but can be done in the car


Should I just get them rebuilt since they will be off anyway?
Zack
08-02-2017, 09:16 AM
Should I just get them rebuilt since they will be off anyway?



Uh, I said they can be changed while in the car.


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PyrBliss
08-02-2017, 09:53 AM
Uh, I said they can be changed while in the car.


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I know. Normally I would just change them in car like you suggested. Just wondering if since the heads are coming off for the forged rod/piston install anyways, if I would be wise to have them rebuilt while I'm at it.
Fastbob
08-02-2017, 09:57 AM
I really think the engine needs to be removed from the vehicle to do a forged bottom end.
Curless
08-02-2017, 10:22 AM
If the engine is coming out, rebuild it...
PyrBliss
08-02-2017, 10:27 AM
If the engine is coming out, rebuild it...



Yeah I'm thinking so. It's out, might as well go through everything and start fresh.
massacre
08-02-2017, 10:56 AM
The OP indicated that the engine would be out for bottom end work. In that case it makes perfect sense to me.

OP you might want to take a look at these, if your heads will be apart anyways. Worth almost 40 at the tire throughout the powerband when timed correctly

https://www.mercurymarauder.net/forums/showthread.php?t=104621&highlight=96-98+cobra+intake+cams
PyrBliss
08-02-2017, 11:44 AM
The OP indicated that the engine would be out for bottom end work. In that case it makes perfect sense to me.

OP you might want to take a look at these, if your heads will be apart anyways. Worth almost 40 at the tire throughout the powerband when timed correctly

https://www.mercurymarauder.net/forums/showthread.php?t=104621&highlight=96-98+cobra+intake+cams


Wow and seems cheap enough to do as well. I will for sure be looking into buying some. Thanks for the tip :D

I wonder how drive-ability will be with these cams coupled with a blower?