Trebuchet03

Changing Your Timing Belt And Water Pump

66 posts in this topic

Eh, I am taking my to the local mazda shop, to replace head gasket and water pump and timing belt they said its about 600.. Which I can see, cause its alot of work :P

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hi all i was wondering on the crankshaft sprocket do you align the keyslot or the notch on the back flange to the notch on the block?, also which set of "i" and "e" do you align on the camshafts since there are 2 sets? smile.gif

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oh and does anyone have any pics showing the technique for reinstalling the timing belt on the camshaft sprockets biggrin.gif

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Step 10 Removing the T-belt

Hand turn the crank until the I and E align and the crank pip/keyway aligns with the notch on the block. When I say hand crank, I mean put the crank pulley bolt in and turn with a wrench. At this point, you'll probably want to remove the spark plugs so you don't have to deal with cyl compression forces. Remember, you will have the belt on at this point. If you are going to be using the same belt, mark the direciton of the belt with a paint pen or sharpie (never reverse the direction once installed).

This might be a dumb question but am I suppose to align the I and E together? or the I with the I and the E with the E?

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not sure if anyone is still watching this thread, but here goes. I changed my timing belt a few weeks ago and even though I had the seals, I did not feel ambitious enough to do the cam and crankshaft seals. Engine ran fine, but things started leaking.

Yesterday I took it all apart to replace the seals. The timing pulley on the crank shaft was a bear!!! took 2 hours to get it loose, anyways I got everything lined up, double checked my I and E and notch on the crank. All looked good.

The engine runs, but hesitates and backfires when you step on the gas. Any idea what it could be? I saw mention of the crank sensor, but the illistration in the manual does not give me a clue as to where it is. All wires seem to be connected.

95 626 LX 2.0

auto trans

Jeff

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Got it!! I found out that the valve timing was off before and the mechanic must have compensated with the distributer timing. I adjusted the distributor and this thing has more power then it has had in years!!!

Jeff

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Gotta start by saying thank you to Trebuchet03. This is great help.

Believe it or not my mother just gave me the keys to her '99 626 that has been sitting for a month. She didn't like how it ran so she went and got a new car. . . We just have to love woman like that, don't we??? :rolleyes:

Anyway, she said it wouldn't start so I purchased a new battery and installed it. Cranked over great but sounded horrid. First thought was interference engine with a bad timing belt. Now I see it isn't an interference engine but am very convinced it is the timing belt. It's got 79,000 miles on it and I'm sure at 73 years of age my mother didn't ever think to do this. I could also hear what sounded like a worn-out idler or two...

My questions are about the cam sprockets. Has anyone ever just used zip-ties??? Seriously.... Why not just use a couple monster zip-ties to hold them together? They could be criss crossed and cinched down nicely, no? It sounds crazy, but it also sounds doable.

the paint dot trick is also a great idea for this project. Thank you everyone that has made this task look much simpler than it did a couple hours ago.

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Gotta start by saying thank you to Trebuchet03. This is great help.

Believe it or not my mother just gave me the keys to her '99 626 that has been sitting for a month. She didn't like how it ran so she went and got a new car. . . We just have to love woman like that, don't we??? :rolleyes:

Anyway, she said it wouldn't start so I purchased a new battery and installed it. Cranked over great but sounded horrid. First thought was interference engine with a bad timing belt. Now I see it isn't an interference engine but am very convinced it is the timing belt. It's got 79,000 miles on it and I'm sure at 73 years of age my mother didn't ever think to do this. I could also hear what sounded like a worn-out idler or two...

My questions are about the cam sprockets. Has anyone ever just used zip-ties??? Seriously.... Why not just use a couple monster zip-ties to hold them together? They could be criss crossed and cinched down nicely, no? It sounds crazy, but it also sounds doable.

the paint dot trick is also a great idea for this project. Thank you everyone that has made this task look much simpler than it did a couple hours ago.

You could probably use zip ties, but this doesn't help you if it's already out of time, or if you need to replace the oil seals. When doing my V6, I didn't find it difficult to align the pulleys at all, I'm not really sure what the big deal is.

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So I replaced the t-belt on our P5 (FS, 5 speed manual) yesterday. Took around 5-6 hours, but that included time wasted cleaning/repairing the cracked upper timing belt cover. I also wasted almost an hour trying to get the darn tensioner spring on there. I also wasn't in any particular hurry.

The car had 109k, original belt. The old one I removed still looked brand new, with almost zero wear, no cracks or fraying. Had I known everything would look this good, I would have driven it a few more years before replacing anything. Oh well.

Here are a few tips:

-I didn't bother removing the PS pump, I found this unnecessary. Removing the two accessory belts, and the water pump pulley were all that was needed.

-I have a new water pump and idler/tensioner pulleys on-hand, but after inspecting my old ones for play I decided not to replace them, and will save the parts for next time. My water pump is tight as a drum and spins smoothly. Nothing like OEM quality :)

-I did install a new tensioner spring; the old one looked fine, and was not stretched, and probably would have been fine for another 109k

-I also didn't touch the cam or crank seals...no indication of leaks from the old ones, I just cleaned up a little oil that had leaked from the VCG.

-After verifying my old belt was timed correctly, I decided to try the zip-tie method...I used 4 regular zip ties, two in an "X" and two straight across between the pulleys, and this was more than sufficient to hold everything still. I used pliers to pull them super-tight before removing the old belt. I also marked with a sharpie the old belt at known referent points on each of the pulleys, and counted the teeth/marked the new belt as a precaution. Note that every 2 rotations of the engine causes the reference marks on the belt to move by two teeth on all the pulleys (the back side of the belt is designed to have the tensioner take up slack, while the front is under higher tension).

-I used a new valve cover gasket and valve cover bolt seals; the old one was brittle, and had seeped occasionally in the past.

-Since I took my spark plugs out to make engine rotation a little easier (not necessary, however), I took the opportunity to re-gap the plugs. 0.040-0.043"

-I didn't need to raise the car or remove the wheels; just turn them to the right, and with an impact wrench it's a piece of cake to get the crank pulley off.

-Like Paul mentioned in his original post, the stud on the motor mount backed out with the nut; I think this is because they overtighten the jam-nut for the ground wire at the factory and damage the threads. In my case, the nut eventually came off, and its threads were stripped (I had never removed it, it was not rusty, and I have owned the car since it had < 40k miles). Fortunately, I have a bucket-o-bolts from the various Mazdas I've torn down, and had a few identical nuts to replace the damaged ones.

I didn't take any new pictures, the original ones Paul posted pretty much sum up what you will see.

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Great Job !
Can someone please post a WALK THROUGH FOR A V6 PLEASE ~
And, where do you buy a new pin for the tensioner.?
It has to be really tough to hold almost 600 pounds of pressure.
Nothing wrong with my old tensioner.
Works great, but how do you find a new pin ?
Any help is greatly appreciated.

 

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So even though this thread is quite old, I've actually got a few things to add, and then a question.  If you've only got hand tools one way to tighten the crank pulley bolt is to put the PS / AC belt around just the crank pulley and the AC pulley and use a vise grip to clamp it down like this:

 

CrankPulleyClamp.jpg

I was able to tighten down the crank pulley bolt no problem like this.  One caveat is that this probably isn't too good for the belt, and I'll probably replace it sometime soon.  I did something similar when torquing down the water pulley bolts.

Another thing was attaching the tensioner spring.  I just used an allen wrench to pull the tensioner all the way towards the engine mount bracket and then held it in place with a zip tie like this:

IMG_20161108_133733.jpg

As can be seen, the two attachment points for the tensioner spring are as close as possible in this position and it only took about ten seconds to get the spring on like this.

Now comes my question.

After I got everything reassembled I started up the engine. I had been running the engine for a few minutes, revved it up to around 3k rpms a few times and started and stopped it a few times. At some point I noticed a strange sound which seemed to be coming from the timing belt area.  If I had to guess, I would guess it was the sound of the timing belt flopping around due to it being loose.  I never heard such a sound from that area before.  I reused the tensioner, the spring and the idler pulley as they all seemed to be in good condition, although I've never done this before so what do I know.

The things that somewhat stood out to me where that it was fairly easy to get the new belt on ( most people said it was a real PITA ), I simply used the allen wrench to turn the tensioner left until the allen wrench hole was exactly to the left of the tensioner bolt.  I put the belt just a little bit over the cam sprockets first, then worked it fairly easily a little onto the crank sprockets, then went around with a rubber mallet gently tapping it into place, a little at a time.  It took under five minutes.

The other thing I noticed was that after I removed the zip tie, the tensioner moved back quite a bit, and the tensioner spring was maybe stretched to 2.5 times it's resting length.  I don't know what's normal here, I don't have any basis for comparison.

I'm thinking that if the noise really is the belt flopping around, then maybe even though there was 100% no noise like this before, and even though the tensioner spring looked fine, maybe it's just not strong enough to deal with a brand new belt?

I'd really like to hear what people think as I'm a bit afraid to drive it till I figure out what this noise is and I don't want to just throw parts at it.

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13 hours ago, sailorbob said:

So even though this thread is quite old, I've actually got a few things to add, and then a question.  If you've only got hand tools one way to tighten the crank pulley bolt is to put the PS / AC belt around just the crank pulley and the AC pulley and use a vise grip to clamp it down like this:

 

CrankPulleyClamp.jpg

I was able to tighten down the crank pulley bolt no problem like this.  One caveat is that this probably isn't too good for the belt, and I'll probably replace it sometime soon.  I did something similar when torquing down the water pulley bolts.

Another thing was attaching the tensioner spring.  I just used an allen wrench to pull the tensioner all the way towards the engine mount bracket and then held it in place with a zip tie like this:

IMG_20161108_133733.jpg

As can be seen, the two attachment points for the tensioner spring are as close as possible in this position and it only took about ten seconds to get the spring on like this.

Now comes my question.

After I got everything reassembled I started up the engine. I had been running the engine for a few minutes, revved it up to around 3k rpms a few times and started and stopped it a few times. At some point I noticed a strange sound which seemed to be coming from the timing belt area.  If I had to guess, I would guess it was the sound of the timing belt flopping around due to it being loose.  I never heard such a sound from that area before.  I reused the tensioner, the spring and the idler pulley as they all seemed to be in good condition, although I've never done this before so what do I know.

The things that somewhat stood out to me where that it was fairly easy to get the new belt on ( most people said it was a real PITA ), I simply used the allen wrench to turn the tensioner left until the allen wrench hole was exactly to the left of the tensioner bolt.  I put the belt just a little bit over the cam sprockets first, then worked it fairly easily a little onto the crank sprockets, then went around with a rubber mallet gently tapping it into place, a little at a time.  It took under five minutes.

The other thing I noticed was that after I removed the zip tie, the tensioner moved back quite a bit, and the tensioner spring was maybe stretched to 2.5 times it's resting length.  I don't know what's normal here, I don't have any basis for comparison.

I'm thinking that if the noise really is the belt flopping around, then maybe even though there was 100% no noise like this before, and even though the tensioner spring looked fine, maybe it's just not strong enough to deal with a brand new belt?

I'd really like to hear what people think as I'm a bit afraid to drive it till I figure out what this noise is and I don't want to just throw parts at it.

I would change the tensioner spring no matter what. It's not worth the risk of damaging your engine, because such of a cheap part.

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This is a non-interference engine, so even if it were to jump time it wouldn't damage the engine.  Anyways, I just pulled the upper timing cover and took a video of it running and the tension on the belt is just fine.  However, I'm thinking that maybe the new belt is putting more pressure on the tensioner and idler than the old belt and it's causing the bearings in them to make noise.  The video will be live in a few minutes:  https://youtu.be/hFZ2v20QCfM

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So it turned out that the brand new water pump was making the noise, but it went away on it's own.  The way we figured it out was we recorded the sound and loaded it into an audio editor to look at the waveform and saw that it was clicking at 16 clicks per second and then did some calculations to see that the only thing rotating at 16 Hz was the water pump.  You can read more about it here if you're interested:  http://mechanics.stackexchange.com/q/38580/7132

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Yeah, it turns out that although it's rare, sometimes these water pumps need a little "breaking in" period.  I asked someone about it:

Quote

 

Water pump noise is not common but does happen. Steady tone noise is more common such as groans or squeals. Rhythmic noise is less common. There are three rotating parts in a typical engine water pump. Two standard type ball bearings and a spring loaded seal. The seal has flat faces that slide over each other. The seal material is often ceramic. The seal needs to slide smoothly, if there is extra friction a stick-then-slip rhythm can occur, resulting in noise. The spring in the seal can be the driver for the rhythmic nature of the noise.

New seals need some run time to burnish and hone the surfaces. Before this they can be noisy and exhibit some seepage.

This is what I learned from a pump seal manufacturing representative some time ago.

 

 

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