Valve Guide Driver

[Xploitn]

I'm going to be replacing some of the cracked valve guides I found, but what is the valve guide driver that people are using? Are people using an OEM special tool or are there non Mitsubishi alternatives?

I saw the FSM had a tool called Valve Seal Installer (MD998728) but I'm pretty sure that isn't what I'm looking for. Could someone verify that?

If nothing else, could someone measure the inner and outer diameter of any valve guides that you guys might have laying around?

 

[AllanL]

may need a machine shop to do this...

 

[JacksonAuto]

Replacing valve guides is usually a machine shop job because it requires some specialized tools and the ability to do a valve job afterwards. You will lose concentricity with the new guides so the seats need to be machined to correct that. It can be done at home but it's not for your average novice or home mechanic. On a difficulty scale from 1-10 i'd put it at a 9 or better.

 

[Xploitn]

Thanks Tony for the straight response.

 

[bjones18]

1. You need a hydraulic press to push them out ( and a crazy angled support block)
2. Pushing new ones in might be harder than getting the old ones out.
3. You need to ream them after install.

Challenging job.

 

[arrowhead]

Do not attempt at home.

 

[bjones18]

I'm not one for posts with motherly advise. I've read E90 BMW forums with complete idiots warning against doing things. I think some of those post writers work for BMW Stealerships. DSMTuners tends to be a bit more fact based. That said, here is my take on it.

a. I have a 20 ton hydraulic press. You need one. this does not make it simple.
b. when you push guide in don't stop part way. You got one chance per bronze guide.
c. you need to measure and push in to correct depth. it sticks out both ends. no positive stop.
d. if you are not happy with a height after push in... buy another set of guides to replace the one you crush trying to adjust.
e. Nothing is square & vertical (your guides push in at ~55deg from vertical) build an angled block to hold head.
f. Angled block must hold head in at different cylinders (1,2,3,4) and top & bottom (push in / push out)
g. Screw up the aluminum hole by dragging a guide in-or-out = scrap the head.
h. If you manage to get all guides out and new ones in... keep reading.
i. You need to buy a specific reamer. You might want to buy two.
j. Reaming is not easy
k. oil or no oil for reaming? Your size will be different.
l. Reamer "teeth" are steel, and flex under load.
m. Ream at ONE drill speed.
n. allow the existing hole to center the reamer (or be really-really accurate)
o. check hole size with valve stem, any sticking is bad
p. If reamed hole is too tight... good luck. A hole that is "almost the right size distorts the reamer diameter different than a fresh guide will.
q. Get this far? Lap valves and check shape on seat & valve.

It has been a few years since I did this. I think I would pay to have this done next time. I've built engines, tore apart trannys, done bodywork, rolled fenders on a $25K car, tuned, fabricated, tig welded and more. Valve guides are a challenge.

 

[BogusSVO]

http://www.dsmtuners.com/threads/how-to-change-valve-guides-in-a-4g63t-head.341218/

 

[keltalon]

Wow at the responses of don't attempt at home thanks bogus for clearing this misunderstanding up. Jeeze! I know the thead is old but people are often mislead through old threads and wonder why their car is not running right.

 

[Archer Fabrications]

You can remove them with an air hammer. But I'd go to a machine shop for the installation. Those things are an absolute bi***.