is it neccesary to replace the valve guides ? engine has 116 k on it..
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is it neccesary to replace the valve guides ? engine has 116 k on it..
The only way to know if there worn beyond spec is to measure them.
From the wealth of information thus far provided, in no particular order, the answers to all your questions about valve guides are, maybe, no, yes, sometimes, often, no, no, yes.
ok so where do i find out the spec's for it?
The factory service manuals should have this info.
If in doubt, replace. At 116K they are probably going to need replacing in the near future. So, if you plan on keeping the car for an extended period of time, replace them, if for no other reason than peace of mind.
Of course, it is possible that they will spec out just fine, but with the mileage, probably not.
Once you develop a "feel" for it, you can remove the springs, etc, and wiggle the valve when it is a little ways off the seat to tell if they are quite worn, if they are close to OK, this method is a bit crude, but if you want to do a quick check you can try it. Unfortunately, one can't spec an amount of "feel" and even then you'd need the FSM to tell you for sure...
Hope this helps!
Mike
Also, where are we?
If we're at "I'm doing a full restore on my car, everything is apart, I'm getting new valves, seats, port job... ... ..." then yes, get new guides.
If we're at "This is my DD and I'm seeing a slight blue puff once in a while and am insanely confident that it's not my PCV valve or Turbo" then no, don't.
Mine needed new guides on the exhaust side... the engine had 126,000 on it, but the intakes were fine. I've been hearing that it's typical on the exhausts with mileage.
Elgin (I think it was when I researched into it) makes the guides, but you must buy $600 worth... I could have made my own, but much less of a hassle to simply buy directly from FWD-P as they have them in stock, and at a VERY fair price, too.
TU and FWD-P also have a majority of the hard to find seals and gaskets.... they are our vendors of choice.
i am at.. this engine had a bad rod knock ..so the engine is apart and doing everything.. head ported and polished, intake and exhaust mani to match, 62mm turbo, +40's injecotrs, and the list goes one.. i just dont want to miss anything while it's apart.. also where the freak to do i find these FSM's? i've got one from ebay but it's electircal only..
Only got specs for the 8 valve here, gives it at the end of the section for that engine type. Given as stem to guide clearance. Exhaust clearance is about double intake, I guess for thermal expansion, so cheapskates might use worn intake guides in the exhaust side :D
Give me a minute and I'll post up details for the TIII. Gotta find my details.
Ditto, I find out most times, the exhaust go due to the heat.
I had some made by my new head porter and still came out cheaper than buying new one's.
http://minigts.com/servicemanual/93_Diagrams/engine/
Let me know if you need more pages. All the pages should be uploaded in a few minutes.
it's the page or two before that in my '90 manual which doesn't have the TIII twin cam specs, only 91-93 have I think.
Sorry, wrong path. Updated with the 93 pages link. Pages 38 and 39.
this one's the winner...
http://minigts.com/servicemanual/93_...I_assembly.JPG
He did you a favor then, because at $9 each... the solid bronze is almost that, not to mention the labor. making guides is easy, but not as easy to make perfectly concentric, which is VERY important, otherwise you need to sink the valves. Chucking in a lathe and drilling the hole doesn't make for a straight and true guide as a drill walks off center the further it drills into a hole.
That's when you use a miniature bar cutter :p .... for shadetree points ... made out of a chip of piston ring tacked to an old small valve stem ...
Not sure what you're talking about bud! But what I was hinting at, is this: every once in a while, we use whatever guides we can source for an odd or obsolete engine. (or for cost cutting reasons per the customer) When the guide is not concentric to the outside of the guide, then the centerline of the valve stem ends up being offest. because of this, the valve job ends up getting way out of whack, and/or you have to aggressively re-cut the seats until you get a decent margin back on the 45. We've had to press back out new guides because of this issue. Also, drilling a hole for the guide... the drill will walk and wander... picture it drilling a path in the form of an "s"
The guides that FWD sells were spot on and needed only *minimal* honing to bring to size.... they were almost right to size as is after pressing in.
Some bronze guides for the T-III surely would be nicer though...
what are the stockers composed of ?