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1G Timing mark trouble

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Tom Gibbons

Proven Member
50
4
Mar 22, 2015
Beecher, Illinois
Hello all, I ran into a problem changing my timing belt. This is a 6 bolt swap in a 2g. I can't seem to get all of the timing marks to line up. When piston #1 is at TDC of the compression stroke, the dowel pins are at 12 O'clock, the timing marks on the cams and oil pump pulley are lined up properly, but the timing mark on the crank gear is not lined up, (about 1/8 revolution away from the timing mark on the block).

At TDC of the exhaust stroke, the cam gear marks line up properly, the oil pump lines up properly, the dowel pins are at 6 O'clock, and the crank gear is in the same incorrect position as it was when at TDC of the compression stroke.

The engine ran alright, but felt a little weaker than I think it should have under high load. I pulled the valve cover to be sure that piston #1 was at TDC and what stroke in the cycle it was on. It seems to me that something is on incorrectly, and I am worried about trying to fix it and blowing up my engine. Any help would be greatly appreciated.
Is it possible that I have the wrong crank timing gear? Or could the marks be off since it's a 6 bolt swap?

These two pics show TDC on the compression stroke.
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I don't really guess anything. however it might keep t-belt/crank sprocket aligned to some degree.

here's how it looks installed pre-belt install

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Is the picture just funny or do the cams look like the are not exactly at 12 o'clock too? Maybe one tooth off up there also or the picture is deceiving. Definitely should put a new crank sprocket on that thing for so you don't skip a tooth down the line.
 
New sprocket, get a trigger plate, and I'd also go ahead and put a new hydraulic tensioner in there too. The one you've got looks pretty corroded, I wouldn't trust it to keep proper tension on my timing belt and risk the chance of skipping a few teeth, bending a few valves in the process.
 
I'm getting the works as far as timing components: tensioner, idler pulley, tensioner pulley, and belt. Balance shaft is already deleted. A new crank sprocket is on the way as well. However I am wondering what is it about the trigger plate that is necessary for timing? At TDC of exhaust and power strokes, the dot on the outer part of the crank sprocket lines up to the same spot every time. I can get everything to line up correctly with the exception of the crank pulley (the dot does not point to the mark on the block). Does the trigger plate do anything besides provide a timing mark? It looks like its for a crank sensor which I thought 6 bolts do not have. And since it is attached to the main sprocket, they would rotate with the same angular velocity so I would think any arbitrary reference mark would work.

Is the picture just funny or do the cams look like the are not exactly at 12 o'clock too? Maybe one tooth off up there also or the picture is deceiving. Definitely should put a new crank sprocket on that thing for so you don't skip a tooth down the line.

Here's a less deceiving picture. I believe they are too high when they line up. This is something that I fix when I take off the belt correct?
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You main sprocket is also missing some teeth. You couldnt attach a harmonic balancer properly. Change that thing. You are not aligned and cant be without the plate.

You're right about this too. Some of the rubber on the inner part of the balancer was torn and I am replacing it with a new one from Oreilly's.
 
It could be that the 7 bolt is different but aren't you missing the crank position sensor? The backing plate is what crank sensor reads.

Also might want to do every seal, crank seal, oil pump seal, cam seals, because that engine was definitely not what I would well maintained

I thought that the 1g CAS provides a cam angle and crank position signal to the 2g ecu. Hence the need for splitting the signal from the CAS when doing a 6 bolt swap.
 
Imagine you're running the car pretty hard, doing 7krpm shifts, maybe hit a bump, and the timing belt just happens to catch a tooth on that balance shaft sprocket. there goes all your timing components, along with your engine. for friggin $6.49, can't you just buy the plate and run the motor how it was engineered to run ?

then add a new 6 bolt oem tensioner to the cart, then all the seals like said above, and be on your way correctly.

I see red rtv around your cam seals, so it looks like they must need replacing.
 
I hate to beat a dead horse ... but this is how these cars get shitty reps and and blown motors. Replace all that old crap. buy the dang plate and do it by the manual. Skimping on this stuff only causes head aches later on.
 
Thanks for all the info guys. Ive ordered the plate and seals too. Im not trying to argue the importance of this trigger plate, but rather just understand how it works. Now i see that it provides a nice barrier between the timing belt and balance shaft sprocket. Believe me I want to fix all the crap this jackass previous owner did wrong, including the mass amounts of rtv under the valve cover.
 
Does the trigger plate do anything besides provide a timing mark?
Yes. It provides a proper (smooth, flat, uniform) backing for the timing belt along its path of travel. There actually are't that many mechanisms that "contain" the belt along its path, so it's best to retain them all.
 
Not trying to say you're not but are you finding tdc the proper way with a degree wheel and picking a point on the up stroke and down stroke, then doing the math to find the precise degree that is tdc? Or are you just turning it till the piston stops going up? If you're eyeballing it there is a chance you're just a tooth off
 
Not trying to say you're not but are you finding tdc the proper way with a degree wheel and picking a point on the up stroke and down stroke, then doing the math to find the precise degree that is tdc? Or are you just turning it till the piston stops going up? If you're eyeballing it there is a chance you're just a tooth off

In his picture there is a screw driver in the #1 cylinder so I would imagine he is using that to measure where top dead center really is.

Like mentioned I would replace everything external to that motor. It looks like a junkyard 6 bolt that sat under a tree in the rain for 6 years and got slapped in for a quick flip.

Crank sprocket
Oil pump sprocket
I would replace the whole oil pump assembly
Oem tensioner assembly
Oem pulleys
Oem cam gears the old ones are yuck
Water pump
And a whole lot of engine degreaser
 
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