tach not working

[Luvoekars]

The tach in our 87 has started not working about 80% of the time. It typially reads too high, and has progresively gotten worse. Now it will easily peg that needle. I'm curious if you guys think this is in the head, or in the drive on the end of the blower? Also, who could rebuild the bad part, or where can I buy new ones?

Thanks,
Adam

[warbucks13477]

Remove the sender and lubricate it before it breaks.

[sfedeli]

Adam, It's probably attached to the back of the blower next to the alternator. Mine has a nice red dust cap on it. Remove the cap and put 3 or 4 drops of oil down into the hollow shaft. Hopefully, you're not too late.

[Don Meyer]

Hello Adam,

If you end up needing a sender, I purchased mine from Lauderdale Speedometer in Fort Lauderdale. Good guys and were very helpful. If you end up needing one give them a call. 1-954-522-4885

Don

PS What part of Venice are you from. My brother lives there and we get over there from time to time. Perhaps we could get together and "compare notes".

[Luvoekars]

We have different places all over town, we own the charter bus company here with 17 MCI coaches. Let me know if you get this way, I'll show you around. We have the Bird, a 1990 MCI Custom Coach, and about 20 pre 1930 antique cars.

Adam

[Luvoekars]

I am going to get the coach out of storage in the next week or two to lubricate the sending unit. What have you guys found is the best way to reach it? I have not had the access from under bed opened. Is that the best way?

[sfedeli]

Adam,

If you are relatively agile, you may be able to get to the sender by reaching in over the battery tray. If there's too much exhaust pipe or insulation in your way, then sliding back the mattress and removing the access panel is the easiest way to get there. You may also want to check the alternator belts for any cracks while you have the access plate off. You'll probably find a 20" by 20" piece of plywood secured with screws beneath the mattress. Under the plywood will be a metal plate secured with 16 sheet metal screws. Once they are removed, pry the lip of the plate up with a flat screwdriver and work it loose. Some of the plates are secured with caulking.

[warbucks13477]

With my coach there is the cruise control system right along side of where I would have to squeeze up over to get to the alternator. I always feared doing damage to that so never even tried. But I guess its possible if you are small and careful.

But Shane has what I feel is a better idea and what I do. One thing that I would change however and that is since you are going to open up the floor inspection plate anyway I change the belts if they are more then 2 years old. For what little cost they are its good preventative maintenance. And I would absolutely and strongly advise you to buy a Kriket from NAPA or on the internet to tension the belts correctly. Unless you frequently replace and tension belts most get them to tight and that is tough on the alternator bearings. http://www.arnnworx.com/krikit.htm
Costs $15.50 at www.amazon.com also http://tinyurl.com/dffjgp

[Luvoekars]

I will probably go ahead and remove the access hatch under the bed. I have had the mattress out and the plywood, and have seen the metal hatch. I know the alternator belts are old and need to be replaced anyway. Before this summer trip I want to remove the hatch again, since I want to replace all the hoses in the engine compartment. We have a 4 week trip planned leaving mid July, traveling from FL to MN with a 3 week old baby (due the end of June), so I don't want any problems.

I've heard the coolant lines to the air compressor need to be replaced, but I think I'm going to do all of the coolant lines, and things like the hydraulic lines to the fan.

My coach has an extra bank of batteries on top of the original batteries, so it would be almost impossible without taking up the hatch.

Adam

[Luvoekars]

I finally got the coach out of storage today to check out the tach. I removed the hatch under the bed, and the tach drive had a black rubber cap on top. I took the cap off and put some oil into the shaft. When I restarted the coach, the tach is still doing the same things. It behaves sporadically, basically reading high, but doing a lot of "jumping." At an idle it will show anywhere from 1000 to 1800, and will easily go to 3000 with any rpm.

Any advice? I hate to just start changing the drive or the tach itself without knowing the cause of the problem.

Adam