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1992 Dodge Stealth RT TT - 1994 Mitsubishi 3000GT ATX
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Discussion Starter #1
So on my newly acquired 94 3KGT SL I was checking the timing covers due to the lower cover section rubbing the power steering belt and pulley. Long story short after removing the covers I got to looking at the timing belt on the cams and water pump. Seemed excessively loose so being an idiot like I am started pulling and poking at the belt until the belt lifted enough off the front intake cam (facing the front of the car) to cause it to snap and rotate under pressure.

I know I know, stupid mistake. I did some searching and reading and I now understand that there will be slack around the water pump when the car has been sitting. The car appears to have a new belt put on already.

So what I'm asking is what would be my best method of approach for resetting that one cam or should I reset all of them??

It definitely moved and the tension on the belt changed when it happened. Slightly but it changed some.

I took pictures and to me it looks like both cylinder heads appear to have the cam dot locations the same as each other if that even matters or there very close. The rear cam dot is hard to see where it is but I've tried to include a picture of it there if you look closely.

I KNOW that there not correct or anything I'm just trying to go about it the safest easiest way to remedy my mistake.

I figured I could just take it back to TDC and go from there but I don't want to damage anything as it is. Also would it help if I had a picture of the crank pulley in accordance to the timing mark?

Any help would be really appreciated and if this isn't in the right location I apologise. I'm still pretty new here! Awesome group though!!

Also the very rear cam gear is different then all the others? Is that normal? Just a different style than the others.
IMG_20200215_132920476.jpg
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Thank you and take care!
 

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you will need to reset everything all the timing marks for each cam gear and crank cog must line up for the engine to run properly and not cause internal interference
release the tension and start from scratch if you turn the engine over the way it is you may cause damage
 

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93 NA ATX 3000gt DOHC
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So what I'm asking is what would be my best method of approach for resetting that one cam or should I reset all of them??
That depends on which way it went and if only one tooth which I suspect would be the case.

I figured I could just take it back to TDC and go from there but I don't want to damage anything as it is. Also would it help if I had a picture of the crank pulley in accordance to the timing mark?
That’s what you need to do and picture of timing mark would be handy. Mark on balancer needs to be on T of indicators on lower timing cover. From cam positions it appears you might only need to rotate crank clockwise ~ 1/2 turn to get to the T indicator.

That's IF you don’t mind taking a chance. I wouldn’t think 1 tooth on intake cam would cause a problem. Maybe you could wait for more experienced to chime in. Or do as HOSS indicates starting from scratch.

Also the very rear cam gear is different then all the others? Is that normal? Just a different style than the others.
That’s normal, that exhaust cam gear is made different because it has cam position sensor plate behind it.
 

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^^^^ correct 1 or even 2 teeth off on a intake would not cause a problem from my experience you usually don't hear the snap of the cam returning to the neutral state if it only jumped a tooth
 

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.......from my experience you usually don't hear the snap of the cam returning to the neutral state if it only jumped a tooth
HOSS might have a good point here. If you could get another picture of front gear set more straight on where indicator marks can be seen between cams along with gear indicators. That would allow comparison of tooth count to indicators, which would allow exact tooth count of jump to be known.

I do recall reading about couple tricks to jump cam gears backwards a tooth without taking anything apart. Would have to try and find again, but it was like using 1/4" (?) piece of round stock laid in gear tooth and slowly rotating engine forward until it can be removed when it reaches belt/gear separation side, forcing belt after round stock to advance one tooth (retarding gear). Another was someone using hard plastic (maybe credit card) feeding it thru to force tooth change, but can't recall what direction of tooth change was goal with this one.
 

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1992 Dodge Stealth RT TT - 1994 Mitsubishi 3000GT ATX
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Discussion Starter #6
Thank you all for replying so quickly and helping out!! I really do appreciate all the support everyone gives here.

So I was thinking and with the situation it seems like it would be best to just take it to TDC and go from there IF it won't damage anything just getting it there.
I would ask whats the preferred method of finding TDC and going about resetting them but I'm sure someone already has a good write up on that. Maybe a link then??

White93gt I don't know if I'm quite understanding what you mean by the picture you're describing?? Are you meaning like a shot of both gears along with the marks on the head looking through the gears?

I don't think the front intake cam jumped a bunch but it did move enough to basically take all the tension off of it. May have been a couple teeth? Idk

Also is there a measured amount of tolerable slack your supposed to have??

Any benefit or cons of using a manual tensioner in a situation like this??

Thank you all very much!! Please forgive me as I am disabled but still extremely busy!

Take care
 

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So Like yourself, only worse. I had just completed my FIRST EVER timing belt on my old 1992 VR4. Took me 13 hours or so...straight. Had never done a timing belt and had no idea about these cars. I just dug in. Did the water pump too which was a nightmare removing the old gasket. But anyways....literally less than a week later I did the same thing you did. Right when I did it I wanted to die. Only choice you have to is tear into it lol. 1 tooth or 20, it doesnt matter, it all needs to be rechecked to be safe. However it is fairly easy to just reset the belt when you dont have to mess with the water pump and tensioner and all that. Luckily It was all fresh in my mind and I think I did it in about 2-3 hours.

Dont think theres a measureable amount of slack, more simple though...just expect slack and dont F with it lol.
 

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.......So I was thinking and with the situation it seems like it would be best to just take it to TDC and go from there IF it won't damage anything just getting it there.
I would ask whats the preferred method of finding TDC and going about resetting them but I'm sure someone already has a good write up on that. Maybe a link then??........
I’m not quite clear what you prefer to do: 1) start from scratch and do complete timing procedure for crank and cams? or 2) Try to correct small change in the intake cam you think may have moved, without disassembly to do entire process.

If #1 whole process: Somebody here may have reference of good step by step. I can only reference the mechanical FSM pg 11-31 thru 11-35, which in my opinion leaves a lot to be desired.

If #2 correct the one cam problem: Then the picture I mentioned would first allow us to determine how many teeth were jumped and what direction it moved. To determine if it’s safe to move crank to jump a tooth and to a point where it can be verified correct. The picture would have to be more like the one below, for us to count the variance between the two cams. Or you could give us tooth count of exhaust and intake from marked teeth to reference indicator on valve cover in between the two gears.
Cam timing marks.jpg

Also is there a measured amount of tolerable slack your supposed to have??
When running there is no slack in belt, it’s all removed by the tensioner. Slack only occurs when engine stops and at times because of compression crank backs up a little, that puts slack in side of belt (right/back) that is normally pulled by crank. If back bank cams are in certain position at that time, valve spring load will move them backwards a little which then drops slack around water pump. Simply turning crank a little clockwise will remove all slack introduced by back drift of crank and cams. Also it will not happen every time engine is stopped only at times.

Any benefit or cons of using a manual tensioner in a situation like this??
There are different opinions of the manual tensioner. I prefer the factory auto-tensioner for same reason as the new preloaded accessory drive belt tensioners. They maintain proper tension of belt without having to occasionally adjust it to eliminate belt slippage (squeal). I’d hate to remove everything necessary to check manual timing belt tensioner on occasions.
 

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Discussion Starter #9
Again my apologies on the late reply! It's been pretty cold here and I don't like doing much with the car then. Anyhow thank you again for the replys!! I am open to basically anything as long as its done an easy BUT correct way whether that be resetting it all or just that one cam.

I tried to get a picture of it put the only time I had the sun was angled just right and I couldn't move the car so I've edited it to be able to see the marks (as best I can on my phone)

If you can give any suggestions with the photo or if I should get another photo, I have nothing pressing me to get it running so I can wait and see what is suggested.

The white paint marks are where the cam dots are. Both cam sets on both heads look to be all in about the same position so I'm not sure if it's supposed to be that way or not but I don't think it moved a bunch?? I really don't know at this point.

If worse come to worse and I gotta reset it all, who has the best procedure for just the timing setting??

I sure appreciate all the help!!! Please forgive the slow response.

Kind regards.
 

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Discussion Starter #10
Thanks for explaining how the slack works. That definitely makes sense. So is there improved wear on the belt with a manual tensioner due to it not being able to "release" the tension?? Just curious.

I guess when I get it all set back all get the covers back on and not worry about it ?

Thanks!
 

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EDIT: Removed the post because I of possible bad info.
 

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Removed previous post about safe to turn engine, because I original said tooth count indicated intake cam was retarded, which would have minimized chance of valve contact... WRONG .... :(

Tooth count actually indicates intake cam is advanced 2 teeth, which makes me question if it's safe to turn engine.

EDIT: To clarify why cam direction of change (jump) is important, retarded intake cam lowers chance of piston/valve contact and advanced exhaust cam also lowers chance of piston/valve contact. Obviously the reverse of either increases chance of piston/valve contact.

From your picture it appears exhaust cam is 11 teeth from indicator on valve cover (assuming still correct), while intake cam appears to be only 9 teeth from its indicator (advanced by 2 teeth). Since that puts intake cam with increased chance of piston/valve contact, without cam degree spec sheet I’d be afraid to advise turning engine. Which would lead me to suggest starting from scratch, doing disassembly and following good practices to correct that cam and insure others are correct.
 

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To answer couple of your previous questions, that were lost with my (brain fart) #11 post.

.......Both cam sets on both heads look to be all in about the same position so I'm not sure if it's supposed to be that way or not ....
Yes both sets should be in same relative position when comparing intake cams to each other and exhaust cams to each other. Your intakes would be about 2 teeth different because of front bank jumping out of time.

......So is there improved wear on the belt with a manual tensioner due to it not being able to "release" the tension?? Just curious
Don’t know for sure, since I’ve never ran manual tensioner. But I suspect wear would be worse with manual tensioner, especially if tension was set to high.
 

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Discussion Starter #14
Hey thank you very much for helping out. I was thinking I could just reset that intake cam because of how easy it was jump time in the first place. So getting it there is the easy part, it's just getting it out on time.

Could you explain how you came about the number of teeth the cams are at?? Do you just count the teeth in-between the sprocket dot and the valve cover mark?

Thanks again and I'm sorry about replying so late. I really do appreciate yalls helps with this
 

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Could you explain how you came about the number of teeth the cams are at?? Do you just count the teeth in-between the sprocket dot and the valve cover mark?
Yep, that's all it's to it and is why I needed a picture more straight on to see dots and marks. Since exhaust cam on front head most likely didn't move, the difference in count between that gear compared to intake cam gear would indicate how much it moved and in what direction.

To confirm just count teeth in-between the sprocket dot and the valve cover mark of all four cam gears and compare count. All should be close to equal (less than a tooth), maybe not perfect because of belt slack. I suspect you'll find front intake cam is two teeth closer to mark than other three.
 
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