noisy quad

[Guest]

Ok, basically the problem is the quad is making a ticking noise, kinda like the cam smacking the lifters but its only coming from the left side of the engine (if you are looking from the front of the car)

Other theories are that the timing chain is to blame, that could be true since the sound is definatly coming from the left side of the engine which is the timing chain side.

I have recorded the sound so you can see what it sounds like.  To be honest it sounds like it is getting worse. I swear it is getting louder.

Click for sound

I have recently changed the oil and oil filter. Oil used is Mobile 1 synthetic 5w-30.  This problem has been happening for more than 1 month, possibly a few months.

When driving, I can't hear the chattering at all (1500+ rpm) This is only when idling.

I really hope I can get this resolved before my long bfest trip, so if you guys have any ideas, that would be great. I would like to have it fixed this weekend if possible. (Timing chain replacement if needed)

[rweatherford]

I'd get in there and check the chain area.  Probalby the chain slapping around on something, but if it is a cam gear coming loose you could destroy the top end of your engine.  It is not worth the risk to not check it out.

[Guest]

Ok so i have the parts I need now, so im trying to get into the timing chain cover...

How do i remove the belt? In the manual it says i need to rotate the tensioner arm counterclockwise, pull the belt off then release it.  The problem is, it doesnt tell you how to do this, the quad's tensioner is kind of in a hard place to get at.

I was thinking I could maybe get a floor jack and a piece of 2x4 and stick it under the tensioner, jack it up so it makes it go counter clockwise, pull the belt off the A/C loop then release it all so I can finally get at the crank pully.

2 other stupid ideas are to just unbolt the crank pully with the belt on it because the belt doesnt seem that tight. The other idea is to pry the belt off the crank or tensioner pully with a screw driver.    

What do you guys do to get the belt off? I want to get this all done by tomorrow.

[92BerettaProject]

I don't know about a 90 quad but on a 91 quad I can get a 13mm wrench onto it and move it to release the belt.

If you're going to have the passenger side wheel off you can reach it easier from under the car.

[Guest]

Thats ok, we got it off. I didnt know what it ment by rotating it. I thought that If i was to try to stick a wrench on the bolt that I would just undo the tensioner. My dad was the one who got it off, i was at work.

[rweatherford]

So what did you find inside?

[Guest]

Well, the gears weren't that worn, look almost identical to the new ones we put in.

The negatives things we noticed were:

1. Small dents on the edge of maybe 3-4 links that were attached to eachother. All the rest were fine so it was probably damage from when they first put in the chain.  

2. There was some wear on the long guide around 1/4 the way up from the bottom, the most severe wear was stretched along around 3 inches of it.

3. directly across from the damage area there is a metal shaft for one of the cover screws (I think. I have been away for 2 days) that has obvious wear. Probably 2-3mm of metal shaved off.

4. The tension on the up side of the crank stroke ( between crank sproket and intake sproket) was bad. The chain could flex enough to be able to hit the metal described in #3.

5. I noticed scratches, more like gouges(sp) in the plastic on the tensioner shoe. They were going across it so it seems like damage from other than the engine use. There are only maybe 5 and not deep, all in a random group.  There was good tenion on the chain.

Overall its not bad, the worn metal is a sure sign of something.

I have ordered a external spring for my new tensioner and new tensioner shoe.  I have replaced the right timing guide with the one out of my junk car because its not worn at all. All 3 sprokets are replaced except for the water pump sproket but its fine.

During this down time I'm also replacing the alternator because it was missing the rear oil seal for the bearings.


I do have one question. I used 7mm bolts as my dowels when I took off the exhaust and intake sprokets.  The intake is fine and timed but the rear is slightly off.  I cant see exactly by how much but I think its probably atleast half the dowel hole.  I cant get the bolt back in. I actually had to unscrew it to get it out because it was on such an angle (not bad but enough to prevent pulling out).   The rear one was slightly off compared to the intake sproket.  So my question is, do i need to re-time the exhaust cam? Can I just get something to stick in one of the 3 holes on the sproket and push it back so its in alignment with the hole?   I really dont think it is out of alignment that much at all.    

I do realize timing is important but im trying to say that its not that much out of time (if it actually is), maybe.. maybe by one tooth to tooth width on the sproket.

If I was to take the sprokets off, the pins on the cams would look almost exactly like the ones in the haynes manual picture.

I have one more thing to ask, have you guys ever noticed how lose the bottom end of the right guide is? I can move mine probly half an inch. Both guides do that.  It seems like its suppose to be like that. Is this right? When you put  new ones in, were they that loose too?

[rweatherford]

On the cam timing and cam sprockets.

I'm not sure but I guess you are talking about the alignment pins that are supposed to align the cam in time, while you install the chain.  If so you can remove them no problem.  Just be sure that the crank is rotated 90 degrees backwards so that the valves cannot hit the pistons.  When you are ready, reinstall them.

If you are installing new cam gears, be SURE that the bolt and dowl pin CANNOT COME LOOSE OR FALL OUT.  If necessary use some Loc-tite.  If they fall out with the engine running it becomes a nasty disaster.

When reinstalling the chain it is important that there is NO slack in the chain between the intake and exhaust gear.  I like to install on the WP gear first, then a cam gear.  Do one first and then rotate the other cam towards the other one to catch the next tooth so they are tight.  If it seems really easy to put the chain on then it is likely that the timing is one tooth off.  Only way to tell is to complete the procedure and after rotating several times, check the alignment pins with the crank at TDC.  After doing the top gears do the crank gear, again, no slack between the crank and intake gears.  If you have to rotate the crank back a alittle to catch the next gear, do it.  Then rotate forward to TDC and take all the slack out.  Doing this will create slack on the tensioner side and you should be able to get the chain over the tensioner.  The tensioner should be locked in it's position before you start installation.  There is more than one way to do this depending upon the design.

After you have everything installed, take out the alignment pins and rotate the crank several times.  Stop at TDC and take a look at the cam alignment pin holes.  The holes in the cam gears should be lined up with the holes in the carrier behind it.  If not try again.  There should also never be any slack in the chain between the cam gears.

There are more than just one design of guides, chains, gears and tensioners, so perhaps you have a mixed set of guides?  Not sure.  It's been a while since I have been into mine.  I have the later design single row chain on my car.

Good luck!

[Guest]

Ok, ive goten everything back together.

The problem I have now is, I was running 5w30 sythetic oil. What happens is I can drive the car for around 10-15 min, it starts nice and there is no chattering, it sounds great. It gets up to normal operating temp. But when you stop at a light or stop sign and the car is idling (1000rpm) the oil presure is down at the 1/4 mark. The timing chain is chattering and grinding in the case. Basicly the lack of oil presure is causing the tensioner not to be able to push up against the tensioner shoe.  I have to push the gas to keep the car at around 1500 rpm just so there is enough presure to make the tensioner push on the shoe to tighten the chain.

If I start it cold, the oil presure is fine because the oil is thicker.

I have tried 10w30 in it now, but that only prevents the problem by only 1 or 2 min then its just as bad.

Since its a band new tensioner, installed correctly. Im thinking maybe my oil pump is going and isnt putting out the proper amount of presure.

I even got a oil guage and screwed it in where the oil sender unit is, I was getting 30psi at 1000 rpm with the hot engine, the incar guage was a little below half before i put the external presure guage on. When i reved to 2000 rpm, the presure was 60 psi.

I didnt check the presure when the car was hot at 1/4 on the oil guage in the car. I figure it should be around 15ish anyway.

So my questions are, do you think i need a new pump?
What level of presure does your guy's car run after you have drove it a while? Does it go down to 1/4 guage like mine?

The car has 250,000km on it and i have no idea when the oil pump was changed, If it ever has.

[rweatherford]

If you change the pump then I would change out the rod and main bearings while I was there, but then why not rebuild the entire motor....  I think you see where I am going..

I'd try some 5w-50 synthetic or 10W40, or 15W40 before I would start changing hard parts.

The tensioner on my car is made different than yours and will not back off when the oil pressure goes down.

[Guest]

I have replaced the oil with 15w40, luckly my dad has a stock pile of it.  I ran it longer than I did before and found that it is helping.  It keeps just enough presure to prevent the chattering from getting to the point where it sounds like it will skip a tooth.  I can hear the chain hitting something and im pretty sure its the metal cover across from the bottom of the long guide.  So basically the car is drivable, I dont have to hold it at 1500 rpm to keep the presure up so the chain doesnt rattle any more.

I have determined that the pump must be at fault, I have ordered a new one. ($300).  NO im not going to redo main bearings, I dont have enough funds to be waisting on this car at the moment. It has already eaten $200 in timing system stuff.  I have spent 2 weeks and taken the timing cover off 9 times trying to resolve it.  Atleast I can go from complete start to tensioner out within an hour now.

[rweatherford]

Yea you start to get pretty good at that....  The oil pump is not hard to do.

[90_Black_GTZ]

Your clatter doesn't sound that much worse than mine has always sounded. ÂÂÂ

Experts, if you were going to reduce the clatter, in what order would you replace hardware, or would you just pop open the chain cover and look for obvious wear and replace those parts?  I'm sure there are a few parts that always wear out before others.

BTW, my car's birthday is coming up in a couple of weeks!  I will have owned it for 16 years.  Now it will be old enough to drive itself.

[rweatherford]

(90_Black_GTZ @ Apr. 24 2006,08:47)Q
U
O
T
ENow it will be old enough to drive itself.
I'd pay money to see that....


On the noise...  Perhaps the double roller chain is just louder and that was the reason for the newer design?  I've never owned the double roller.

[Guest]

I changed the oil pump and it still doesnt sound good.  It helped and its keeping just enough presure on the tensioner to keep it form flaping around to bad but I can definatly hear it tapping metal and I think its hitting one of the inner case poles, if u can call it that.. im gona try some things this weekend to try to create a little more tension.