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Time to talk to a real machine shop.
They can:
1) make a new one from rough stock
2) knurl yours if not too bad
3) repair yours by sleeveing
4) repair yours by other method.
Anything made by man can be re made by man.
 

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Valve guides can be bought by size instead of part number.
Google took no time to find these guys, there are lots of others. Call them with dimensions from the Service Manual (Section 1).
 

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Guide Liner Installation Procedure Detailed - YouTube
A good machine shop (automotive) should have this
I have done a similar job except instead of lining the guide is knurled. Both are a solid repair.
Not likely you'll want to buy the tooling, although I did for knurling, but a good shop that does a lot of head work should be set up already.
I did Dodge 225 guides as well as Gardner Diesel guides.
 

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I've replaced dozens:
Warm head to about 300F
Drive out old guides, drive in new ones
Cut new valve seats piloting on the new valve guides
Easy as pie with the right drifts and a set of 3 angled seat cutters ($500?)....And some experience.
It should cost about 1 hour labor in addition to the price of 3-angle seat cutting.
 

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If you, or your shop is careful when setting up you don't even have to re cut the seat (unless it needs it) when knurling or lining the existing guide.
I'm just suggesting this if getting a new guide is difficult. It works and is not expensive.
It doesn't sound like the OP'er is going to be doing the job himself, so I suggest if he is going to pay an automotive machine shop, pay for one who will solve the problem, either by procuring new guides or repairing the old ones.
I've worked on many engines that parts were either out of production or un obtainable in an acceptable timeframe, and there are alternatives to "replace with new".
 

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Maybe we could do a combined order and then Priority Mail the appropriate parts across the US. :unsure:
I should mention timing is a factor here... my last Skandix order took over a month to arrive. Can you wait that long on the head? I've no idea what options are, if there's an actual choice, what your shop is willing/able to do, etc.
 

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Discussion Starter · #92 ·
Valve guides can be bought by size instead of part number.
Google took no time to find these guys, there are lots of others. Call them with dimensions from the Service Manual (Section 1).
Not sure exactly what you googled, but I didn't find all that many. The ones I did find get close, but don't have appropriate sizes/shapes.
 

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I think in the age of computers probably part numbers are correlated with dimensions in a highly reliable way. If you put in Saab #7560154 el machino is going to know whether there is a part that fits those dimensions and whether there's a cross-reference pretty quickly.

I suppose the advantage of talking to someone is that they might have a better search tool that could quickly find guides with a correct OD but is too long or too small inside that a machine shop could modify. Like:


The ID is slightly too small (.2610 vs .2742), and the length is quite a bit too long (2.365 vs. 1.92) but the OD is in spec.

I'm pretty sure my cost on that work would exceed importing them from Germany, though.

Edit: I did my math wrong, forgot about valve:guide clearance. Whatevers.
 

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I think what is important is to focus on what you want to achieve and not how you get there.
New guides are one way, but we don't replace a block because the bores are worn over std size, and you don't have to replace guides because of a little wear. What you do need to to bring them back to the correct dimensions,
If your guides are broken, worn into a "D" shape or in some other way un repairable, than buying generic guides and machining them to fit is a viable option, but if the just are a few thousandths oversize then you have far more options.
If the machine shop you are using doesn't do this kind of work, then either find another shop or have them see about sub contracting the repair.
I know if it were me, I would not be waiting for expensive shipping and replacing guides in an aluminum head if I didn't have too. Yes, it can be done and is done often, but if you don't need to why do it?
Keep your eye on the prize, not how you get there.
 

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Discussion Starter · #96 ·
Well...the machine shop just called and said they found some. So academic at this point, but still curious on the iron vs. bronze issue.
 

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The biggest issue with bronze guides is that they need to be specially clearanced. I'm sure the factory specs are for iron... bronze has a difference thermal expansion rate and cannot (should not) use similar clearances. If the manufacturer supplies that information or the shop knows something about the motor they should be good. That said, ITM components are generally not great - my shop won't even install their stuff. Still, when options are limited...... Some companies - Ferrea comes to mind - make some really nice bronze guides. You just gotta know what you're doing with them.

I don't understand the cutover... it may be part number confusion. I think all 1986-1993 16vT heads are the same and use the same guides. In 1991, the non-turbo went to a 2.1l motor that uses a different guide, so you've got 1986-1990 NA which is a 49mm guide and then 1991-1993 NA which is a 45mm guide. This may not be all of it - I definitely see people saying the 1990 cut applies to all motors. I don't know why. :/
 
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