Trippin’ gauges..related to bad tensioner?

[cotto]

Hey Guys,

Lately I here found that my volt meter has had erratic readings. Today my volt meter read unusually low (at and below the dash line just left of center) and after checking the rest of my stock gauges I noticed the oil pressure was unusually high (just past the dash line right of center) and temperature gauge was reading warmer than normal. The weird part is that as the volt meter occasionally went to back to normal, for a short time, so would the other three gauges. This kind of freaked me out so I went to the local Schucks and had the voltage system checked, all is good. I then checked my oil, the level was normal. Now all that being said, after having my valves adjusted by Cummins Northwest about a month ago, they had noticed that I too was in need of a new belt tensioner relatively soon (original tensioner w/ 190,000 mi. ). Since then I have been keeping an eye on it and I have noticed that while the truck is running it does dance and jiggle more than Jennifer Lopez. As well, the belt is riding about a 1/4" off the pulley toward the tensioner arm. Could these two things be related? Could a loose belt cause my gauges to go awry, do to a lack of tension on the alternator? I checked thread achieves, I couldn’t find a similar experience. I did buy a new Dayco belt tensioner ($100) which I will be installing tomorrow for preventive maintenance. So I guess I will see what happens, but what do you guys think?

 

[Philip]

Could a loose belt cause my gauges to go awry/QUOTE]



Probably not.



I would check the dash ground first. They are located behind the OD switch plate. The are mounted onto the metal plate behind the dash board. If you drop out the cover under the steering column and looked up behind the OD switch plate you can see the grounds.



Also clean up the body ground. This is the small wire that comes off of the neg battery terminal. When the truck was assembled. There was paint under the wire terminal. Sand the radiator support and reinstall the ground wire.

 

[JLEONARD]

I second the motion to check and insure a good ground.

This can cause lots of issues.

Jay

 

[cotto]

Once again, thanks for the info. Having the location of the grounds will help speed up the process. I'm going to check the ground tomorrow. I hope that fixes it. I hate electrical problems. For me they are always just trial and error.

 

[JLEONARD]

For me they are always just trial and error.

For me too, but I made so many errors, my first trial is always the ground.

Jay

 

[dpuckett]

$100 for a tensioner?? I gave $50 for my Dayco from AZ. Hated to buy there, but it was a name brand, and they have a nationwide warranty.



Also, there is a small, insignificant- looking wire going from the ground on the battery, to the front support. Check it; I had it loosen up on my 92 D350 (now Mom's), and it pegged the left hand gauges, and the right ones went to minimum. Put the ground back on, and everything was back to normal.



Make sure the shop didnt accidentally (carelessly) knock things askew. I had a shop one time knock all the return lines loose on a 6. 9 IDI Ford- careless, or looking for more work, cant really say.



Daniel

 

[JLEONARD]

Make sure the shop didnt accidentally (carelessly) knock things askew

Daniel,

Nice restaint and choice of expressions.....

I would have said "frig up the riggin'" or words to that effect... as in "expletive deleted".



Jay

 

[Paychk]

Any time you have multiple bizarre electrical problems, always check the grounds. 99% of the time, that will fix all!

 

[cotto]

Well guys, thanks for your input. Mystery solved. Chalk another one up to the wisdom of the TDR members. You educated another lame-o. Although a simple fix, it was something I would have taken a while to diagnose. I first checked the sheet metal bolt used to ground the body to the battery. It was very loose. I bent the teeth down on the o-ring wire connecter and tightened it down and all is good. Side note, I also put in my new belt tensioner. I found the tensioner from Autozone for $50 with a 3 month warranty. Smuck’s sold the exact same Dayco part for $100 with a lifetime warranty. Unfortunately, A Z did not have it in stock and the nearest A Z is over 20 miles away. Smuck’s wouldn’t even do the “Price Match” guaranty because of the difference in length of warranty. What a crock! The original tensioner lasted 190,000 miles. I have no idea where I'm going to be in the next 190,000 miles. Who needs a frickin’ lifetime warranty for a tensioner? I’m kicking myself, but I sprang for the $100 Dayco “special” from Smuck’s for shear convenience. Although it was not related to the electrical problem, the belt is now back on track in the middle of the pulley. Giddy-yup. Oo.



Thanks again,

Cotto