Strange Engine Noise

[Tyler Jaxon]

I am the owner of an '87 Volkswagen Golf with the 1.9L ALH TDI from a '98 Jetta, I've owned it a little under a year and bought it mostly done (swapped and driveable). For the first several months it was running and driving perfectly and as it should, no strange noises or problems. During fall of last year I started noticing a distinct droning noise coming from the belt side of the engine. Not to be mistaken for a ticking sound from the valves, it is a sound that I cannot find the source of, the timing belt is tight and still good, the serpentine belt is newer and there's no problems with it. The previous owner that did the swap did not know how many miles were on the engine, but it ran very good and still starts up and drives just fine, I'd like to find the source of this noise though so it doesn't cause any future problems. I thought about taking it to a diesel shop but I'd like to get some input from people who may have experienced something similar before. Thought it might be the injection pump but I'm not too knowledgeable on this stuff. Only other diesel I had was a 7.3 powerstroke. Thanks, I will post a video of it running as soon as I can.

 

[Abacus]

Was the engine from a 1998 Jetta, which is an AHU, or was it from a 1998 Beetle, which has the ALH? Your post is confusing because there was no ALH in the 1998 Jetta, but there was in the 1999.5 Jetta.

As to the sound, remove the serpentine belt and see if it’s still present. If it is, you can rule out certain things and it could only be a handful for what’s left.

 

[Tyler Jaxon]

Sorry I got the years mixed up as far as the ALH and AHU go, It is an AHU. I will do that next chance I get to work on it. Thanks!

 

[Mozambiquer]

I am the owner of an '87 Volkswagen Golf with the 1.9L ALH TDI from a '98 Jetta, I've owned it a little under a year and bought it mostly done (swapped and driveable). For the first several months it was running and driving perfectly and as it should, no strange noises or problems. During fall of last year I started noticing a distinct droning noise coming from the belt side of the engine. Not to be mistaken for a ticking sound from the valves, it is a sound that I cannot find the source of, the timing belt is tight and still good, the serpentine belt is newer and there's no problems with it. The previous owner that did the swap did not know how many miles were on the engine, but it ran very good and still starts up and drives just fine, I'd like to find the source of this noise though so it doesn't cause any future problems. I thought about taking it to a diesel shop but I'd like to get some input from people who may have experienced something similar before. Thought it might be the injection pump but I'm not too knowledgeable on this stuff. Only other diesel I had was a 7.3 powerstroke. Thanks, I will post a video of it running as soon as I can.

Post a video. Sometimes the alternator clutch pulley will make a noise like a droning, or sometines it gets replaced with a gasser alternator without the clutch pulley. The 90 amp ones didn't come stock with them, but the 120 amp ones did.

 

[Tyler Jaxon]

I'll post a video of it, I still need to pull the serpentine belt and start it to see if it still makes the sound.