Things that make you go....WHAT THE &^%???

This site may earn a commission from merchant affiliate
links, including eBay, Amazon, Skimlinks, and others.

mac

mac

Crew Member
Joined
Jan 7, 2005
Threads
121
Messages
1,156
Location
Wet Coast
Some strange happenings with my fresh 1HD-t. I've out 1500kms on the new motor now and have had a strange noise from the get-go. It sounds like a rotating noise, a scraping as though the fan was hitting the shroud and is very consistent with RPM's, it doesn't change when hot or cold and doesn't seem to affect performance. It seems to be coming from the lower portion of the timing cover but it is really hard to pinpoint- at times it sounds as though it were coming from under the valve cover.

Things I have done: removed all belts to isolate water pump/ alternator. Pulled inspection plate at bellhousing- nothing odd there, no filings, etc.. Changed the oil through a strainer- not a thing for the magnet to pick up. Pulled the T-belt cover- small amount of belt dust but nothing obvious that would create a noise like that. Removed the harmonic balancer and inspected- looks normal w/ no evidence of rubbing. Pulled the vacuum pump. I'm not quite sure how tell if one of these is healthy- this one seems to create vacuum but when turning by hand several revolutions will be consistently smooth and then followed by a couple of hard turns. Also, my brakes have been acting funny intermittently- like they are applying themselves and sticking on. Could this be related to the vacuum pump?

I've removed the glow plugs and have turned the engine over by hand but nothing is jumping out at me. I hear the clicking from the IP and I think also from the injectors but I'm not sure how those components should sound. Next step will be removing the timing cover- I'll have the it torn down to the short block at this rate!

Any, ANY ideas would be welcomed. Sorry for the book...
 
Does it have a new timing belt idler?

Did you put the pump on 1st then fit the outer timing case cover(the alloy part)? If not the pulley may not be firmly seated on the pump shaft.
It was a tip from an engine rebuilder when I had my 1HZ rebuilt.

I would run it with the plastic timing cover removed

Try putting you finger over the hose from the vac pump it should build pressure to 7psi and then a valve will open on the pump.
Advice I received from landcruiser wrecker is that the vac pump generally lasts the life of the motor and then some more
 
You can run it briefly, 5-10 minutes, with no belts on at all. That would resolve your curosity of any internal issues.

Karl
 
DON'T run it without the timing belt, I think last comment was for alt belts.

Some injection pumps tick and it may be related to the cold start device. Mine does, but it only has the ACSD housing base (homebrew modified).

Without hearing it I can't help too much.
 
For Mods/Site Owner

rick_d said:
Without hearing it I can't help too much.
Click to expand...

Note to mods: allow attachments of sound files. A LOT can be told from the sound.
 
crushers said:
harmonic balancer
Click to expand...

Care to elaborate? What am I lookin' for cause there is no visible degradation. I was thinking the H-balancer too as the noise is consistent w/ crank RPM's and not cam RPM's.

I've run it w/out the belts already- no change.

It's 100% not the cold start device- I've blanked that off.

New T-belt tensioner. Felt good when installing but I'll remove the T-belt and have another look. I will look closely at the IP shaft and pulley as I did mate up the rear housing and pully before torquing down the block mounts. But again, the noise is consistent w/ crank speed which is different than IP pulley speed- right?.
The Vac pump looks to have been changed once as it has a smear of yellow paint on it as though it was replaced w/ a used one. I'll test the PSI when I put this all back together.

Cheers Boys! Thanks again.
 
Update: Well the t-belt tensioner was off kilter a bit. The collar that the bolt goes through that holds the tensioner bracket in place was pressed too far in causing the tensioner to be misaligned, thus the belt dust and markings on the back of the belt. This was a defect in the new tensioner assembly. That was straightened out but I'm still hearing the noise. I think it's lessened though and it leads me back to the H- balancer. I assembled it slightly different than before, rotating the front half to as closely as possible line up the two divits on the face of each pulley. I'm not sure that this is how they should go or if it even matters. Is each pulley half balanced to be installed in a certain position? I may try to find another balancer to try and see if it makes a difference.
 
They have some marks for fitting the belt and then you rotate the whole engine and everything should align on some other marks.
Im not sure why they do it that way except to maybe make sure the belt grooves are perfect.

Have you tried running the engine without the plastic cover on?
 
Well, I believe that the harmonic balancers on the 1HD-t like most diesels are a two-piece unit. They function *roughly* kind of like a centrifugal clutch. When the engine spins, both parts of the harmonic balancer spin but as there is vibration or shaking the outer part of the harmonic balancer catches with the crankshaft side in order to dampen the vibration. There is a kind-of clutch material between these two. When the material goes out, I have seen them throw the outer ring on the highway or make loud screeching noises. The best way to test it is to remove all the accessory belts and spin just the outer ring. If it spins too easily (you'll know) or has obvious degredation then that's your issue. Hope this helps -Todd
 
roscoFJ73 said:
They have some marks for fitting the belt and then you rotate the whole engine and everything should align on some other marks.
Im not sure why they do it that way except to maybe make sure the belt grooves are perfect.

Have you tried running the engine without the plastic cover on?
Click to expand...

Thanks Rosco, but no problems with the timing belt end of things now. Those marks I understand. I'm speaking of the two halves of the Harmoninc Balancer or crankshaft pulley.
 
dieseltoyz said:
Well, I believe that the harmonic balancers on the 1HD-t like most diesels are a two-piece unit. They function *roughly* kind of like a centrifugal clutch. When the engine spins, both parts of the harmonic balancer spin but as there is vibration or shaking the outer part of the harmonic balancer catches with the crankshaft side in order to dampen the vibration. There is a kind-of clutch material between these two. When the material goes out, I have seen them throw the outer ring on the highway or make loud screeching noises. The best way to test it is to remove all the accessory belts and spin just the outer ring. If it spins too easily (you'll know) or has obvious degredation then that's your issue. Hope this helps -Todd
Click to expand...

I don't believe the 1HDT balancers function that way. The inner portion is keyed to the crank and the outer portion is bolted to the inner. They appear to have hard rubber centers to absorb vibration. I guess my question is- are these two pulleys balanced independantly or do they need to be mated together in such a way that results in their being a balanced unit? The TDC mark does not go right across both pulleys but exists on only the inner pulley. Maybe I'm just peeing up a rope here, I don't know...
 
Ok, another update. I decided to remove the H Balancer and run the engine briefly and guess what?- no more noise. It looks like the balancer was the culprit. It's virtually impossible to tell by looking at it because it looks OK with maybe some age showing in the rubber center.

I did a VW diesel recently that sounded like it had a rod knock but what was really happening was the timing belt pulley's integral key had worn the keyway on the crank and it was moving slightly making a noticeable racket. This is a common 1.9VW problem and is also associated with a poor harmonic balancer. The fix is ugly. Remove the crank and remachine the nose, upgrade the pulley to later d-style and replace the H-balancer with an upgraded one. $$$

Hopefully this fix will be just replacing the balancer.
 
brownbear said:
How old is the engine? Any chance of warranty
on this part?
Click to expand...

No, this is off of the old motor- new motor didn't come with all of the accessories. So this balancer has 250k kms on it and I'm wondering if it may have been damaged by the failure of the previous engine. It would have been shaking violently given that one rod was running on a bare journal with no bearing.
 
Or it had inherently caused the problem by introducing a vibration/off balance situation. Leading to crankshaft failure waay down the road.

I think just get it out of there then.
 
You must log in or register to reply here.

Share this page

Back
Top Bottom