My TII had 140k stock mi. on it before I "put it to rest". All of the seals were intact when I opened up the motor. The engine had compression #'s of approx. 95-90ish and 85ish about 4 months before I began taking it apart.

I have kind of a side question; what makes the compression get low? Is it because the seals are starting to wear and not making a good seal, or is it due to wear on the rotor housings (and therefore not making a good seal as well)?

Anyways, what do you guys think, would you reuse these housings? If I rebuilt using these housings, should I expect similar compression #'s, or since I'll have new seals, should I expect better #'s? Thanks for any response... Oh, is the dark coloring on the housings just carbon build-up, or is it 'damage' of some sort?

Thanks:

 

I believe a scotch brite pad will clean those marks off. As I understand it, those darker marks are where compression slipped through. Looks like you had one bad apex seal??

 

hard to tell by the pictures, if there is much pitting then i would can them. another important thing to check is the housing thickness variation tests, if it is out of spec then you may be able to have them lapped unless they are near the minimum thickness already.

 

Measure for warpage via the FSM specs.

-Andrew

 

Can anyone tell me how to check for 'pitting'?

 

looks usable but not great. cant really see the pics all that well, but looks like some chrome flaking on the sides. expect a max of 100 psi compression if youre lucky, but you can make a decent running engine with them.

general rule fo thumb is if any of those marks are scratches deep enough to catch a fingernail, dont use it.

pat

 

any areas where your fingernail will catch when running it accross the surface is pitting, the worse the pitting is the more loss of compression you will have.


i can't really see any pitting in the pics but it is hard to tell.

 

There are many things to consider when re-using a housing. Those black marks should clean off with a very non abrasive pad. scotch pad works, combined with atf. The surface around the whole housing should be smoothe to the touch with no pitting. The pitting youll most likely find is just above the oil metering whole. A bit is normal on a high mileage housing. Also, check the cooling jackets, and the two lines where your coolant seals meet the housing. Check for cracking around the plug hole. But yah, the surface being smoothe is most important. The more smoothe, the more compression.

 

well I think that is slightly good news. I'm at a friends house right now, but I'm pretty sure the surface is smooth enough that I wouldn't be able to catch a fingernail. If it turns out my parts are out of spec (also thinking about my apex seal 'slots') what kind of a shop would I have to go to, to get them machined back in spec?

Does anyone else think the dark coloring is due to a bad apex seal, like 'The Spider' suggested?

 

Could you have a good mirror chroming place or plating place rechrome your housings if they just have the chorme cracked off?

 

ttt

 

I would use them if you dont have any deep scares. Or dont you llive like 45 minutes from Atkins , just take them over to them and ask what they think. They are real cool about helping out with things like that. On the note of compression , I have very used housings on mine and about 3 hours of run time on the rebuild with about 60 psi on both. If i had to do it again i would use new housings just for the insurance of high numbers. good to hear from you and good luck

 

No, the chrome has to be as very specific thickness, densitiy, etc. To my knowledge, a chroming shop cannot be specific enough.

 

i thought it was a little a to far out to be a possibilty, would be cool to able to do though

 

Yeah, I could probably take them down to Atkins. Those guys are VERY cool. I went down there to buy the rebuild kit, and I kind of expected them to be dicks or try and get me to buy more than I needed. Turns out my fears were completely unfounded. Those guys were SO helpful, they hooked me up with everything I needed. One of the guys even gave me an extensive tour of their facilities, fixed the idle on my N/A and let me watch them fully disassemble an FD motor, stopping whenever I wanted so that I could ask questions about the tear-down process. It was the COOLEST experience I've ever had regarding cars.

Anyone else car to elaborate?

 

damn ... that extremly nice .. i would love to have watched that

 

Are those pics in the bathroom? If so I've always considered doing work in there.

 

chrome flaking off where the boot of the apex seal rides in the housing is fairly normal, i have some flaking in my housings. when it starts to be more than a few millimeteres wide and more than a couple inches long is when they are considered scrappable because of the loss of compression. a chrome shop i wouldn't expect would be able to repair the flaking or rechrome a housing because like a paint job it all needs to be stripped down and re-layered to a specific thickness so it is fully bonded and within spec again to work properly.


be sure the thickness variations of the housings are within spec.

 

Before they offered to let me watch, I had no idea of what to expect when taking the motor apart. Watching them do it first took nearly all the anxiety out of me doing it. I had no idea it could be taken apart so quickly. They were seriously completely done in 15 minutes, and that's with me stopping them every minute or so to ask a question.

 

ha ha, yeah that's in the bathroom, lol. I've never actually done work in there. The reason I took the pics in there was cause the lighting was a little better.

Can anyone else give me a yes/no answer?

 

well if you are on a tight budjet go for it . I did , but i wish I had new .guitarjunkie over on the other fourom has just finished a reduild with something like 100 psi or so right off the bat. or run like m9ine at 60psi all the way around and hope to hell that keeps climbing .I put i sweet half bridge on it . It sounds mean. Good luck