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-   -   valve guide replacement (http://www.peachparts.com/shopforum/tech-help/89232-valve-guide-replacement.html)

stevebfl 03-21-2004 06:28 PM

Michael, if you use standard guides you sure won't need any heat.

If you try and ream the head chances are your going to ruin it. The method I use as I expressed works and saves those heads. By using the extra interferance fit the guide will conform to the slight irregularity of the hole. This will cause the inside of the guide to be slightly disturbed also. That is the reason for the reaming after installation. You can heat it if you need but using the proper MB drivers there really is no need. At the proper interferance it will go in about two to three times harder than the slightly oversize standard guides do in a virgin hole (one that hasn't dropped a guide - any movement is dropping in my mind). after near 30 years of doing this and hundreds and hundreds of heads, I only offer advise. If you don't do something on those droppers, it will be one short valve job. They will be slightly out of round and I'd love to see you match the head hole to one of the oversize 14.2 or 15.2 guides. Remember that after screwing the 14.2 there is only 14.4 remaining and then its a new head or some real heroics.

samiam4 03-21-2004 08:25 PM

Steve,

Don't bother telling someone with a few hundred hours in the machine shop how "I'll ruin the head by reaming it". It's the correct way- if you know what you are doing.

As far as having "MB correct tool." Honestly, current mechanics crack me up! You really could learn to save a bunch of $$ by learning basic metal working and heat treating. I made my 0M617 go-nogo gauge in less than 20 minutes out of drill rod, heat-treated, tempered, polished to the final dimension. Very simple and not hard. If I need a correct driver, I will just choose some steel and make one.
I had general machine shop stuff at the university and made rack & pinion, a couple of really sweet flywheels, a full set of heli-coil install tools, etc etc..
Horology school added the precision into my work- ever work with a shaft pivot shaft diameter of 0.03-0.04 mm?

I know what your saying on loose guides and for that matter-seats. Dealt with it all before.


Michael

stevebfl 03-21-2004 10:17 PM

Yea smarty pants, tell be how many loose valve guides have you fixed.

My information was delivered for those who could use it. I just talked to a guy who wanted to buy seals for a 70 dollar master cylinder because he couldn't afford it. There isn't but a few automotive machine shops that do the kind of head work you are talking correctly; let alone a bunch of DIYers. I gave the advice so standard guides wouldn't be used in a place that couldn't work.

xp190 03-24-2004 11:14 PM

Valve job done
 
For anyone who might be interested, I just finished putting back together the two cylinder heads that needed some repairs. In the end I decided that since this car is not worth much, not much money will be spent on it, so the old valve guides were reused. All were within specs. I made a tool to readjust them all to their correct height, and although they will drop again, by that time I hope I won't be needing this car anymore, it's just a winter beater and a back up car so I can do so quality work on my benzo. The heads were resurfaced, degreased, adjusted, valve seals were replaced, leak down test shows that they still hold very well. Tomorrow I will start putting the car back together, hopefully it will run when I'm finished with it ;)

wish me luck.

xp

manny 03-24-2004 11:22 PM

Good luck. ;)
Btw. Have you found a new women yet ?

xp190 03-26-2004 09:57 AM

Manny you devil :)
 
Is it that obvious that I'm looking for one? :)

xp

manny 03-26-2004 11:08 AM

You're always screwing around with your cars........may as well do the same with a women. :D

xp190 03-27-2004 11:49 AM

so true :)
 
Manny you just made my day, I can't remember when i laughed so hard :D

but it is true, now that summer is around the corner I should switch from cars to women, for some reason doing both did not work out very well for me last year :cool:

xp

xp190 04-01-2004 11:12 PM

Almost set
 
The car is back together, only have to reattach the hood and some splash shields which I don't care much for at this moment.

Right now the old choclate milk oil is drainning, I will leave it like that for the night and tomorrow a fresh filter, fresh oil, and I'll see if the car runs, I sure hope it does.

It took me 4-5 weeks to get all this done, little at a time whenever I could.

xp

xp190 04-04-2004 09:35 AM

it wont start
 
I got the car back together, put in all the fluids and tried to start it after checking the timing numerous times. It won't start.

The starter motor turns, everything spins, but it won't ignite. It floods with fuel. I know there is good compression since I checked everything and after a few seconds of cranking the starter motor has trouble turning the engine since the fuel is getting compressed but not ignited. I check for a spark and there is one, although a bit faint. I checked the timing on the distributor, and although I have never used a timing light before, from what I know it seems right.

I marked the crankshaft pulley on TDC, and although I had some trouble checking the marks while the engine was cranking, they did line up as far as I can tell. Still it would not fire.

I think one of the ignition coils might not be connected right, or the wires got broken along the way since I preatty much had to move all of them out of the way, so this is what I will be checking next. Other then that I'm not sure why it won't start.

Any suggestions what else I could check?

xp

psfred 04-04-2004 11:41 AM

Firing order and crank position senor -- if you have the coils wired wrong (I'm assuming distributorless igntion) the wrong cylinders are getting spark, it won't run.

If you have a distributor, make sure you have the wires in the right order and the rotor is actually pointed to the correct one (easy to get the dizzy in one tooth off, for intstance).

Otherwise, no spark is a bad crank position sensor or loose wire somewhere.

Peter

xp190 04-04-2004 12:40 PM

at TDC
 
So at TDC, should the dizzy be pointing right at the #1 cyinder contact?

I did have it one tooth off, I corrected that but still nothing. I'm suspecting something electrical since all the wires were moved around.

xp

psfred 04-04-2004 01:02 PM

Yup. Make sure you didn't get some spark plug wires swapped around, too!

Check all the wires to sensors, etc -- easy enough to pull a connector loose and not see it. You should get a nice, hot spark off any farily recent ignition system.

Also check the coil to distributor wire and plug wires -- when they get old, the insulation can crack when you move them around, and the spark will then "leak" out along the way to the plug!

Peter

xp190 04-07-2004 09:32 PM

No dice
 
Alright, I checked all the wires, I get a nice spark on all cylinders, yet no start.

I tried fooling around with the distributor some more thinking that maybe it's on in the wrong position since there does not seem to be any fuel burning going on at all. No exhaust fumes from the tailpipe. Although after sitting in the garage for a while it did back fire on me. intake mainfold filled up with smoke of some sort, but that was it, nothing afterwards.

I guess next I will check for fuel if any. since I can smell it, I guess it's there, but that could be from priming only. The computer does not report any codes other then batter recently disconnected.

I'm at a loss here, I need some ideas to get this thing to run.

Someone help :)

xp

FrankR 04-07-2004 10:08 PM

The Mitsubishi/Chrysler 3.0L V6 is famous for valve train problems. Here's a link to the factory rebuild manual:

www.twingles.com/manualcd/dsmgift/6g72.pdf

Here's a DIY guide for the job:

http://www.allpar.com/mopar/3fix.html

and another:

http://www.allpar.com/eek/ValveSeals.html

Lastly, if you'd like to buy replacement rebuilt heads from a competent rebuilder at a reasonable price, here's a link to a rebuilder that many offroaders who own Dodge Raiders and Mitsu Monteros have found to be their choice:

http://www.cylinder-heads.com/automotive-cylinder-head-rebuilding.html

Good luck!
Frank


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