Strange Noise and no Tachometer

[Disco_Momma]

I need a little help or suggestions. Two weeks ago a high pitched noise started coming from the engine, and the tachometer stopped working. I popped the hood and it was coming from the alternator. The noise would go away and the tachometer would start working and then it would stop all over again. This went on for a week. So.... last night I bought a new one and put it in only to find the same issues popping up...no tachometer and high pitched noise. As soon as I put it in everything was working fine but when I took off down the road it started all over agian. HELP!!!!!! ANY SUGGESTIONS PLEASE!!!!

 

[Str0ud]

Alice, Welcome to the DiscoWeb. You will probably find the answer to your question here, give us a little more to work with. What year, series of truck are you working on? Again, welcome to the board, it's a great resource for information on your Land Rover.

 

[Disco_Momma]

sorry about the lack of info..hehe

I have a 1999 Series I, V8, 4.0 Disco. Thank you so much for welcoming me. Happy to join, and very excited to learn more. I found that this may be the best way to get answers, resources are few and far between without these groups.

 

[Str0ud]

Alice, I suspect that the strange noise is more probably the tension pulley located directly below the alternator on the drive-belt. The tensioner may be replaced as a whole or there are bearing kits available. I would try to fix this situation first to see if it clears up the tach problem. A slipping belt could wreak havoc with the electrical system. If it does not, I guess, and it is a guess, it could be a bad connection, sensor or ground. Good Luck, let us know how it shakes out. Maybe one of the more knowledgeable members of the board will have solution to your problem, and will jump in on this thread.

 

[Str0ud]

The Haynes Service and Repair Manual is of great help in maintaining these trucks as well. I purchased mine at Books4Cars. It seemed like the only place I could find one.

 

[andrewv]

Stroud: I think you're right on the money. If the tensioner is failing, the tach will get goofy because it's gets it's signal from the alt. (all driven by belt). Welcome to dweb Alice, but I'd get the workshop manual as opposed the Haynes

 

[Disco_Momma]

I would have to agree with both of you on the belt issue. I will try that. I was also talking to another guy about this and we were talking about the problem being in a belt that is routed wrong and the connector which attaches to the back of the alternator being filled with dirt. I have cleaned it off once already, but it could still be the issue....not sure.

As for the manual issue, I spent all day trying to find the one I wanted to invest in and the Haynes manual only went from 89-98 models, would that work with mine. Is there much of a jump in changes between models? The other one was the "Discovery Repair Manual," which was $149.00 (YIKES!!!!) but I am willing to invest if it will benefit me. I can do my own repair work, I just need the guidance especially since I am a baby to the Land Rover world. I LOVE IT THOUGH!!!!!!! I don't care about the fix it issues, I am learning aren't I?!?! Thank you guys for your help, it is greatly appreciated.

 

[Disco_Momma]

One more thing, since this issues comes and goes does that not seem like an electrical problem? For instance, is there some sort of sensor for the tachometer or something like that?

 

[Str0ud]

Alice, The Haynes will get you started. The 89-98 Manual is the one you want if it's a 99 Series 1. It will give you the basics for maintaining and troubleshooting. Discovery Repair Manual goes way more in depth. I'm sure it is worth the money also.

 

[Str0ud]

Well if the tensioner is bad and the belt is slipping, the alternator is spinning at varying speeds. Therefore varying power output to the electricals.

 

[Disco_Momma]

Ok great, I was thinking about it. Even though my Disco is a 99 it is still a Series I...DUH (see I just move so fast I don't think about things) so...the Haynes Manual will work just fine and well I don't drop 149.00 (yet anyway, to fix something that may be so simple).

I do see your point with the belt and it affecting the electrical. I will check over that tomorrow. If this does not work I was thinking about taking it to the dealer to run a diagnostics test, before I make it worse driving it around.

 

[Disco_Momma]

Thank you for your help. Tomorrow is a new day. I am bound and determined to fix this. If you think of anything new though I will be back, tomorrow.

 

[Str0ud]

Way to get after it Disco Momma.

 

[Disco_Momma]

 

[SandMan]

Alice,
Our StrOud is the offical D-Web welcoming and re-welcoming commitee. Yes, by himself he is a commitee. Luckily, he hasn't been committed yet.

Here's my 50 Cent worth ... having replaced the alternator and received no-joy, I might think belt like the others too.

However, since you are hearing a high pitched whining and not a loud squeeking, I'd move to the tensioner bearing next. Metal on metal is a distinctly different sound than rubber on metal.

Replace or rebuild that sucker like StrOud mentioned and you will hopefully be Tach Happy again.

SandMan

 

[Disco_Momma]

Thank you Mr. Sandman. We shall see today what the deal is. I will let you guys know. Although I will probably be on all day asking questions. Hehe

 

[Disco_Momma]

Update

Well.... I got together with some guy friends of mine and what do you know..... there was no noise and the tachometer worked. Although, as soon as I pulled out of the parking lot it started again, and by that time I was too far into traffic to turn around.

Even though nothing was happening, they looked at the belts and messed around with things and said it was fine. Then the noise would come back and the tachometer would stop working over and over all day.

Although, I found the Discovery Repair Manual.....it should be here in a couple of days.

 

[Str0ud]

Yeah, It is common for the belt to only slip under load (while driving). When the pulleys vary in speed.

 

[Disco_Momma]

Well I hate to say it but I think I better take into the shop. I have tried everything (at least within my means). I am going to have them run a diagnostics test. UNLESS ANYONE CAN THINK OF ANOTHER WORDS OF ADVICE?!?!?!!?

PS .

THANK YOU GUYS SO MUCH FOR THE SUGGESTIONS. You still could be right and I am just missing it....who knows but thank you guys for the help.

 

[Str0ud]

Good Luck, Hope it doesn't cost too much. Let us know what it turns out to be.