D'oh, might have cursed myself

[upcruiser]

...by talking up how reliable our Rover has been. On the return from Amado by way of canyonlands the D1 got a couple of hiccups. As we hit Silverthorn, CO the tach started working intermittenly with no effect on anything else. It was parked in our driveway for the past couple of days as I unpacked and cleaned it. I took it for a drive yesterday and now he speedo isn't working and the truck missses above say 3000 RPMs or so. Any suggestions as to where to start? I am thinking it could be related to the reference sensor? I hadn't picked up a service manual for the truck yet so I am a bit in the dark here.

 

[upcruiser]

Oh and it is a '95 D1

 

[lake_bueller]

I'm trying to remember what caused a similar problem with my old '97. I think it was related to either the alternator or serp belt. The battery is another area to check. A dieing battery can cause some weird problems also.

I'd recommend checking discoweb but the site is down (again!). Another good site is http://www.lrrforums.com/

Also...are you getting any codes?

 

[upcruiser]

I'm trying to remember what caused a similar problem with my old '97. I think it was related to either the alternator or serp belt. The battery is another area to check. A dieing battery can cause some weird problems also.

I'd recommend checking discoweb but the site is down (again!). Another good site is http://www.lrrforums.com/

Also...are you getting any codes?

The battery seems fine, I recently put a new serpentine belt in and I am not getting a check engine light at all. I don't have an OBD scanner.

 

[lake_bueller]

The battery seems fine, I recently put a new serpentine belt in and I am not getting a check engine light at all. I don't have an OBD scanner.

The '95 wouldn't need the OBD scanner. There is a small black box under the passenger seat (I think it's that side). The box would display the codes on the '94-95 Discovery.

I'd start by checking the alternator output. After that, the VSS.

Muskyman is better at this than me. Maybe he'll chime in with some advice.

 

[evilfij]

No tach = alternator bad

Start it and see if you are getting 12v or 14.4v

 

[rovertech]

...by talking up how reliable our Rover has been. On the return from Amado by way of canyonlands the D1 got a couple of hiccups. As we hit Silverthorn, CO the tach started working intermittenly with no effect on anything else. It was parked in our driveway for the past couple of days as I unpacked and cleaned it. I took it for a drive yesterday and now he speedo isn't working and the truck missses above say 3000 RPMs or so. Any suggestions as to where to start? I am thinking it could be related to the reference sensor? I hadn't picked up a service manual for the truck yet so I am a bit in the dark here.

The tach signal is taken from the alternator. If you have just replaced your belt make sure you routed it correctly. It is possible to route the belt two ways one of which has the belt running over the top of the alternator to the AC compressor and PAS pump. This causes the belt to have a tiny contact patch on the alternator pulley which will wreak havoc on the system. I have rerouted many belts for customers with this same issue. Check that first then have the alternator checked. Also make certain you have no corrosion in your battery cables/terminals. A corroded ground or lead wire will be a headache. Lastly check the power leak that goes to the engine compartment fuse box. A corroded or broken lead will also cause similar problems. Hope this helps.

 

[upcruiser]

You guys are awesome. Thanks for the patience with a Rover newb. I went out and started it and noticed immediately that the batter was weak. The truck started and the tach was working, which according to what you guys have stated led me to believe the alternator was charging at least somewhat. After about 4 minutes of it warming up, the tach went dead. So I shut it down. I went to restart it and it fired right up telling me that the alternator was charging the battery till that point for sure. The belts are routed correctly and turning the alternator with no problems there. The battery terminals seem fine though the top of the battery could use some cleaning, I can't imagine that it is bad enough to cause a drain of that sort. I think it is the alternator crapping the bed. Will confirm it and check back in.

 

[94Discovery]

You guys are awesome. Thanks for the patience with a Rover newb. I went out and started it and noticed immediately that the batter was weak. The truck started and the tach was working, which according to what you guys have stated led me to believe the alternator was charging at least somewhat. After about 4 minutes of it warming up, the tach went dead. So I shut it down. I went to restart it and it fired right up telling me that the alternator was charging the battery till that point for sure. The belts are routed correctly and turning the alternator with no problems there. The battery terminals seem fine though the top of the battery could use some cleaning, I can't imagine that it is bad enough to cause a drain of that sort. I think it is the alternator crapping the bed. Will confirm it and check back in.

you might have a faulty diode in your alternator remove it and take it to an alternator shop and they will check it .
if you want to clean the top off you battery us some backing soda with water to neutralize the acid .

 

[pangaea]

Kristian,

Great to get a chance to meet you down at the Expo... FWIW, Chalk me up as a +1 on the alternator. That's virtually identical to the problems I experienced when the alternator started to go south on my Disco.

Drop me a line if you need a hand.

 

[evilfij]

Don't buy a crap alternator. Buy one from will tillery aka www.roverguy.com and tell him you want the magnito mirelli one he sells for serp trucks. $250 or so (lists for over $600). The "bosch" ones that are for sale everywhere suck and the cheapo rebuilds are even worse. I bought a bosch for my 1995 LWB and it died in 2 years/<20k and the stories or the remans that autozone sells are legend.

Ron

ps no affiliation with roverguy

 

[lake_bueller]

If you were back in Michigan, I could get you a replacement alternator in about 1 1/2 hours. But Evergreen, CO is a little too far for me to travel:sombrero: But I do miss wheeling in CO.

 

[James86004]

You really need to have a voltmeter. They are a cheap tool. Do what evilfij said and put it across the battery with the engine running - 14ish volts means it is charging, 12ish or less and it is not. Also, an easy way to check the battery is to measure the voltage while you start the engine with the engine cold. If it drops below 9ish V while the starter is cranking, it is either not charged or bad.

 

[evilfij]

You really need to have a voltmeter. They are a cheap tool. Do what evilfij said and put it across the battery with the engine running - 14ish volts means it is charging, 12ish or less and it is not. Also, an easy way to check the battery is to measure the voltage while you start the engine with the engine cold. If it drops below 9ish V while the starter is cranking, it is either not charged or bad.

Hack (aka ron good) method is to turn on the headlights with the truck off and see if they get brighter with it on. :sombrero:
not brighter = bad alternator

 

[lake_bueller]

Whatever you do....PLEASE don't go to landroversonly for advise!! Anyother window-licker just asked about removing the covers from his lug nuts:drool: