The Top DSM Community on the Web

For 1990-1999 Mitsubishi Eclipse, Eagle Talon, Plymouth Laser, and Galant VR-4 Owners. Log in to remove most ads.

Please Support JNZ Tuning
Please Support STM Tuned

Timing issues, won't turn with belt on

This site may earn a commission from merchant
affiliate links, including eBay, Amazon, and others.

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

skyrone

15+ Year Contributor
230
1
Jul 12, 2007
Gillette, Wyoming
Alright guys so I have searched but only have my phone so it's difficult. I will try to include all info I can. I bought this 98 gst that had a six bolt swap. When I got the car it had a bad head gasket as I was told. The car ran but very poorly. Tore it down and had the machine shop go through the head said I had bent valves and a warped head. Got a seven bolt head from a friend and threw that on there today everything went well. Swapped the six bolt cams and rockers over to the new head, it already had valves spring etc. Got the timing all together and can only rotate the engine a quarter turn either way. And it feels like hitting valves. Triple checked timing marks , balance shaft gear is missing but I rotated the oil pump multiple times and retired still no difference. Any ideas fellas? I need to get on the road tomorrow
 
Make sure you have the correct hydraulic tensioner arm and pulley

If you have the 6 bolt arm and the 7 bolt tensioner pulley, it will lock up.

Remover the timing belt covers and spin over by hand in the movement range.

Also look at the back of the pulley, you may have bent it to allow the 1/4 turn movement.
 
And make sure your HLA's are bled down.
 
The cams spin freely with the Belt off. The crank spins freely with belt off. Head supposedly came off a running vehicle. It seems like the timing is just off somehow. I checked and it looked like the cams were compatible and everything. I've tried multiple levels of tension with and without the auto tensioner just to see if it changed and no difference, is there any other compatability issues you guys can think of? Six bolt block, seven bolt head, six bolt cams and gears,
 
If you have the 6 bolt tensioner pulley and it is clocked in the 5 o-clockish position then that pulley is dragging on the front motor mount bracket and is locked up. I timed my six bolt that way and sure enough, the pulley, when tightened down, would lock up on the front (timing side) motor mount. Try clocking it at the 11-12 o-clock position and it will rotate freely. Been there done that. First time, the motor was in the car and it started smoking the timing belt so I quickly turned it off and it took a while to figure it out. This time the motor was on the stand and next to a 7 bolt build, so I looked over at the other motor for a guide but that was the difference, 6 bolt 11-12 o-clock, 7 bolt 5 o-clock or so on the two little holes for the tensioner tool. Check that out. :thumb:
Mine is also a 6 bolt block, 7 bolt head by the way.
 
6 bolt driver side mount with 7 bolt tensioner arm

Also check the mechanical tensioner, IIRC that pulley will lock up too if you put a 7 bolt pulley on the 6 bolt
 
This is all solid info guys but it's not lucked up completely. I can rotate the crank a quarter turn in either direction. There's a lot of movement but it comes to a point where it just stops. As cylinder one is coming up towards the the exhaust valves seem like they are wide open by looking where the cam lobe is at. I feel that my issue has to lie in the timing. I can't imagine whoever worked on this before would have pulled the balance shaft gear and left anything in there and it also ran before this head swap so I'm doubting that. I might just try a new tensioner and new belt and see if that does anything but im still doubtful because it ran with the old head. Idk this new head supposedly came from a running head but I guess I Don't understand how a bent valve or anything would be causing my problem.. The cams spin fine with the Belt off and I can see all the valves cycling.
 
If you have +1mm valves, the intake valves can hit the exhaust valves when both are fully open on the same cylinder.

Check cams to make sure both dowels are at 12 o clock.

If you have one at 12 and the other at 6, this may cause your issue.
 
Both dowels at 12 o'clock. Took cams directly from one head and put into the other. Don't think I could have swapped them and when I investigated this I figured the intake was the only one that has the sensor hookups anyways correct? I will check this again because there is no guarantee it was right on the first place. The gears are identical as well correct? I see no markings indicating intake or exhaust
 
Cam gears can be swapped with out issue,

Only the intake cam will have the slit in back for the cas (DSM)


Only thing to do is drop the timing belt, and remove the pulleys and inspect for scrub marks.
 
scratches, gouges, dings, dents, paint discoloration..

Marks that should not be there, But there by other means than the manufacture process.

I had a timing belt lock up on me on a 6 bolt w/7 bolt head.
Everything turned just fine, until hyd tensioner was set, and lock down bolts torqued.

It was a few years back and I can not recall exactly what part locked up, it was the arm or one of the pulleys,

I remember having to clearance the arm, and I want to say I dented a pulley too.

Just an odd deal
 
I dented the lip on my 6 bolt tensioner pulley when it was installed with those adjuster holes facing down, that's what locked up my pulley. I gently formed it though. Dale, my head had standard size valves and it still bent the exhaust's up when they were hanging open due to not bleeding my HLA's for reference. OP, were the HLA's bled down? They aren't holding the valves open, even the slightest bit are they?
 
Well guys I buttoned her up and rolled it outta the shop. Got a 300 dollar buick to get home with. The lifters might be the culprit I wish I had more time but graduation is in two weeks and I gotta get back to school. I will be sure to get back when I fix it, i found several other threads where people had the same problem but never posted the solution. Also getting back to an actual computer will aid Mt research I'm sure. A phone with a broken screen is not the best tool
 
Wish you the best. Just tryin to let you know what happened to me. Post back.
 
Back at it again. Bled the shit out the lifters thought that was it for sure, no change. Got another seven bolt head and realized that the first one I got was actually a six bolt. How did I find this out? now that I have the head off yet again I realize the thermostat housing won't work with this head. I'm about to burn this car down. Think I'm going to run this six bolt head down to the machine shop ND check it for bent valves. Idk what else it could be at this point
 
everything spun fine by itself with the other components in the neutral position. the balance shaft looks to be eliminated. i am slightly curious if the shop that did the swap did the elimination correctly however it did run before i ever messed with it so i am not sure what the problem is. the head looks as though it has been milled once already so maybe the machine shop will figure something out for me.
 
the machine shop got back o me and said there were no bent valves, he says that he saw where they touched but that they had not bent. if the valves arent bent im really running out of ideas. Ive searched a couple threads about bleeding the lifters and i am still not sure how to tell how theyre all the way bled. They are all able to be pressed by hand. A few of them don't go down as far as the others and ive tried bleeding them again. Any special tricks to this? I got all new timing components coming tomorrow, on the slight chance that the belt is overstretched or for the wrong engine or something. I just wouldn't guess that a wrong belt would be close enough to look right or that a stretched belt would throw it out enough to make the valves kiss the pistons. I just dont know what else could be the problem
 
Support Vendors who Support the DSM Community
Boosted Fabrication ECM Tuning ExtremePSI Fuel Injector Clinic Innovation Products Jacks Transmissions JNZ Tuning Kiggly Racing Morrison Fabrications MyMitsubishiStore.com RixRacing RockAuto RTM Racing STM Tuned

Latest posts

Build Thread Updates

Vendor Updates

Latest Classifieds

Back
Top