[RobJ]

Hi all,

A few weeks ago my water pump started leaking, so i decided to replace it and my timing belt.

I didn't fiddle with the timing (since there were no dramas with the old belt) and put everything back together in the order suggested by the workshop manual and using their reccommended torque specs.

The beginning of the test drive was fine, but by the end I couldn't drive up hills in 2nd gear.

The next weekend I opened everything up and found that my timing was now out by 25 degrees. I reset the timing, again followed the workshop manual and ran into the same problem. This time my test drive was fine when driving normally; when I pushed it my timing immediately went out and now my car has such shitty power it can't even limp up my driveway.

Here are pictures of the steps 9 and 10 in the install that I suspect are the culprit:'



and



When I do up the tensioner stud and tensioner bolt to those torque specs the tensioner plate cannot slide. Is that normal?

The workshop manual i'm working off is available here: http://www.4x4.in.th/manual_sj413/chapter3.pdf - See page 50

Please help!

[cairns27]

I suppose there's no way the crank pully has come loose ???


bye

[miloking]

It is meant to not slide once tightened (its a short belt it wont stretch much in its life time), you can even remove that pre-tension spring after you do that.. they tend to rust/fall apart and fall into the timing cog.

[tonyevans]

If the key's in the pulley's are OK then the only way the timing can change is if the belt jumps cogs and that can only happen if the belt is too loose. When you adjust it make sure that it is sitting in the groves on all gears and not on top of any of the teeth.

[fordem]

Make sure you're using the right timing belt - I seem to recall there were two, with different tooth profiles (one rounded, one rectangular), match your belt to the pulleys.

[jdk81]

Assuming the belt is correct, and it is tightened correctly, and the bolts on the crank and camshafts are to spec

Is the dissy bolt loose?
On my project build I forgot to tighten the dissy bolt, and on the test drive the power went through stages of awesome to gutless.

[RobJ]

I don't think the Crank pulley is loose, when I turned the engine by wrench before reassembling it certainly didn't move.

It's possible that i didn't get enough tension out of the belt before tightening everything up, I just left that to the sprung tensioner pulley while I turned it over about 4 times before tightening everything up.

As for the belts, according to the ebay shop mine came from, I should have had a round toothed belt (which they sent) but when I saw my existing belt, it is square toothed and the round toothed belt definitely didn't fit (it's a shorter belt). The cut-outs on the pulleys are also squared, not round.

I also signed that the notches on the belt were in the grooves, but didn't check EVERY cut-out.

At this point I'm thinking I'll slightly over tension the belt before tightening everything up. That said, I find it really hard to get rid of the little bit of slack on the side of the belt which doesn't have the tensioner pulley. Any tricks here?

[RobJ]

Oh, and I'm pretty sure my issue is cam timing, not ignition timing. I didn't touch the dizzy except to take off the cap and check it spun as the engine was cranked.

[RobJ]

Oh, and another question.

How long can I run the engine for without any cooling system before I risk doing damage?

Ideally I'd like to give it a rev or better yet drive up a hill in my street before reassembling to see if I've forced the slipppage under load.

[tonyevans]

It is very easy to get the belt on top of the teeth under the crank pulley and not notice - And I would think you would over heat well before going up any hill without cooling unless you are in Alaska or Siberia

[RobJ]

In winter, Canberra isn't far off

[shandy92]

Fine to start and idle for a bit without coolant, wouldnt suggest driving tho.

[RobJ]

My car troubles continue.

I cleared out my cooling system again, exposed my timing belt and called a mobile mechanic. The markers on the crank and cam lined up when rotated, but the mechanic uncovered that I had my cam timing out by 180 degrees (when it first skipped it jumped by a LOT, not just a little). The mechanic corrected the set everything at TDC, reinstalled the belt (which he confirmed is the correct belt), slightly overtensioned it to compensate for the stretch in the tensioner string (the same way I had) and put everything back together. Again, the car appeared to drive fine.

I drove pushed it hard on local hills and drove it to work (about 15km, mostly at 100kmh) and it was fine. Driving home however, i felt power loss and it was driving rough (the only way to keep it at speed was full throttle), so I drove it as close to home as I could before an intersection forced me to slow down and I stalled. The car wouldn't start.

I talked this through with my mechanic and he suggested that rather it now be a timing problem it could be something incidental, he had noted that my spark plugs were in pretty bad shape.

I was skeptical, as my car was again at the point where it wouldn't hold idle for extended periods and hitting the gas would almost immediately stall it (revs would rise to about 4k then it would die).

However, I bought and installed new spark plugs. The first two attempts to start the car with the new plugs installed resulted in stalls, the 3rd attempt the car idled and ran normally.

I again did my hard hill test drive, and it was fine. Then I drove it to town (about 8km max speed 80kmh) and then hours later driving back it died again.

At the moment it will hold a natural idle for about 30 seconds then die. Adding throttle will make the revs rise slightly then stall it. - It's pretty much in the same shape it was in after the mechanic reset the timing but before I changed the spark plugs.

What are your thoughts?

I'm thinking that having my timing so far out could have gunked up my spark plugs and Carb (maybe)?
The way it is behaving it sort of feels like a fueling issue now. That said, I have NOT checked whether the timing is still correct since the mechanic had a look.

Please help. I'm running out of ideas and the whole saga is getting me down. I want my Suzie back

[HarryHoudini]

Back to the mechanic is probaly the best course of action,getting a timing light on it to see when/if its firing is the first step,if it won't idle take the plugs out and spin it on the starter motor to get some idea of when its firing,rocker cover off to make sure the valves are opening in the correct order,if all that is OK it may be fuel related.

[cairns27]

I've had the element inside a filter come loose once, caused similar problems...shake the filters, don't just look at them..clamps loose ?

bye

[Goldnomad]

If it's a valve or ignition timing problem, it won't run fine one minute and like a pig the next. My guess is a fuel problem. Either carbie of fuel filter or fuel pump.

Robert

[RobJ]

Without having done anything, except winch it onto a car trailer then leave it to sit in the driveway for a few days, my car is again idling and running normally.

What the hell could be causing it to spas out after it's been run for an extended period or run at speed?

(post timing belt tweak, it died driving back from work, then I replaced the spark plugs, then it died driving back from the lake)

How can I test for the source of the problem?

[Gwagensteve]

With a timing light.

[RobJ]

If I bought a timing light myself, what would I be looking for?

Just that all 4 cylinders are firing?

[shandy92]

Thats would be a good start if they are ahah, search on youtube how to use it.

Short story, put lead on #1 cyl spark plug lead with arrow facing front. Point gun onto timing cover marks, read what number that light flashes on.

That number is ur degrees for spark before tdc (top dead center)

[tonyevans]

It seems obvious to me that your mechanical skills are being stretched beyond their limits with this and you should really look at taking it to a competent mechanic who has experience with this type of engine.

[RobJ]

Working on my car isn't just about getting it running. It's my hobby. and, for me, learning more about how my car works and what do do when something goes wrong is worth the time and frustration of doing it myself, where I can.

I'll take my car to a mechanic where I'm worried I'll make things worse, or when I have no idea what to try next. The reason I love this forum is the wealth of knowledge on here and that someone has always been happy to help when I've run into issues.

I feel like knowing how to diagnose and fix this sort of problem is a skill worth knowing.

[RobJ]

You are right, though, Tony.
I haven't played with timing before. Changing my clutch has been my most involved project so far.

[tonyevans]

Auto mechanics are taught by somebody who knows already how to fix things and then build up a large knowledge base over the years - If you find a good one they will be only to happy to tell you what they found and what they did to fix it - then you can add to your knowledge base as well.

We must all stand on the shoulders of others to see further up the road as my old Granddad used to tell me.

[cairns27]

Directions for safe use of the timing light will be printed on the packaging..


bye

[cairns27]

..but having broken-down many times, my pick is fuel.



bye