By Bryan Crosby (Bcroz) on Monday, October 01, 2001 - 03:57 am: Edit

I have a 95 Disco with 66,000 miles. I have a tapping or knocking noise that my mechanic swears he cant hear. Rockers have been replaced, I've run valve cleaner through, it's not a gas type knock so I havnt tried premium (yet). The mechanic said alot of the knocking is based on the fact it's the old buick engine and the noise is something to live with. Not the answer I'm looking for, any suggestions besides finding a new mech? What should I have checked?

By Robert Mann (Oldscout) on Monday, October 01, 2001 - 06:01 am: Edit

When does it do it ( RPM range)? It could be as simple as a bad oil filter. I would make sure you have good oil pressure before going on a hunt for other causes.

By Bryan Crosby (Bcroz) on Monday, October 01, 2001 - 06:09 am: Edit

RPM range is from idle to about 1300 rpms. Oil pressure was checked and is fine.

By Robert Mann (Oldscout) on Monday, October 01, 2001 - 06:26 am: Edit

Go buy a mechanics stethoscope. It may be a lifter that is not pumping up or rod/main bearings. Noisy lifters can be some dirt stuck in the oil hole or bent/worn push rod. Worn bearings most times can be swapped with new ones and the engine can go one with out a rebuild.

How long ago did you replace your rockers? Did you do both sides? They may need to be shimmed again.

By Daniel on Monday, October 01, 2001 - 06:48 am: Edit

Robert,
I am hearing a similar type of sound. My truck almost sounds like a diesel sometimes until it warms up. I have been told (by a mechanic) that if it is indeed a lifter, the gas mileage would be bad. Is this correct? He also told me that what I was hearing was normal, but this was after the truck was warm.
If it is dirt in the oil hole, what is the remedy?

By Bryan Crosby (Bcroz) on Monday, October 01, 2001 - 06:58 am: Edit

I had both rockers replaced within the last few months. My gas mileage is still 13/17. My mechanic also said some noise was normal. We ruled out bent lifters (said the truck would run like crap it indeed the lifter was bent.

By Robert Mann (Oldscout) on Monday, October 01, 2001 - 07:04 am: Edit

A lifter can go bad many ways. They can stop spinning in there bore and cause rapid cam ware ( flat lobe). They can get varnished up and not adjust properly or have a foreign object not allowing full oil pressure , so they will not fully pump up.

A oil based cleaner is always the first step. I have had good luck with a product called Seafoam. If there was no joy after running Seafoam I would use a stethoscope to find the offending lifter and pull it. You can use a dial indictor to check for the proper lift before pulling the rocker shaft.

By Daniel on Monday, October 01, 2001 - 08:08 am: Edit

Robert,
Is Seafoam something that would go in the oil itself to flush the system? I assume the oil would be changed after???
Also, where or what stores could I find it?
Thanks,
Daniel

By Bryan Crosby (Bcroz) on Monday, October 01, 2001 - 08:44 am: Edit

Daniel

I found Seafoam at Carquest (on sale for $4.95) added it directly to the crank case. It has several uses (all engines). Works instantly to clean your engines innards. As of now my knock is gone, we'll see how long it lasts. Thanks for the tip Robert.

Bryan

By Kristian on Monday, October 01, 2001 - 09:31 am: Edit

Bryan- Are you sure it's not your camshaft hammering against the engine front cover? I have a '95 as well, 115k miles, and mine has been had the hammering noise on and off for at least the last 50k miles. The last time I asked a dealer mechanic about it, he said there was a cam "button" that could be installed to stop the play. Due to the repair labor cost, I chose not to do the fix.

By Stephen Lincoln on Tuesday, October 02, 2001 - 12:09 am: Edit

I have had that sound for a long time and have posted messages before without anything substantial being found. I think it is something like cam shaft end float and I also have learnt to live with it.
I also find it is more prominant after a long drive when the engine is hot.

By Bryan Crosby (Bcroz) on Tuesday, October 02, 2001 - 02:24 am: Edit

I talked to a mech last night, found out the problem lies in a design flaw in the valves in mid 90's discos. Seems rover was trying new valves, and used them over the course of 2 1/2 -3 years. Result is they carbon up quite easily and short of a valve job there is not a long term fix. Reduce the carbon, use Seafoam or something like it, and dont baby the engine (drive it like you stole it someone said in another posting). Also, during the summer months, use a mid grade gas and during colder months use regular (87 octane). Face it, a Rover will never be the quietest thing on the road, just, at times, the only thing moving on the road.

For all its quirks, still the best damn 4 x 4 I've ever owned. It's kind of like the 73 MG midget I used to own, quirky but enduring to the end. I made the mistake of selling my MG, I wont make the same mistake with a Rover.

By Leslie N. Bright (Leslie) on Tuesday, October 02, 2001 - 02:32 am: Edit

"Also, during the summer months, use a mid grade gas and during colder months use regular (87 octane)."


Wait a sec...

I'm under the impression that the lower grades are exasperating the situation... I agree with use of a cleaner, and "driving it like you stole it", but I'd do it on something 90 octane or higher....
IMHO, YMMV....

-L

By Bryan Crosby (Bcroz) on Tuesday, October 02, 2001 - 02:47 am: Edit

Dont know, he said when it got colder, a lower octane was ok. The manual says 87 or better but if I hear that's a no-no I'll switch. Maybe I should start another topic and get a consenses.

By MTB on Tuesday, October 02, 2001 - 02:51 am: Edit

I use seafoam for injector cleaner. Like Bryan & Robert said you can use it in the the engine. But in my town we only have it at a Full service garage. Will try in the engine before next oil change.
If you can't find it try a marina or leave your E-mail address and I'll send you a can.
I'll respond tonight if you do.

Michael B

By Daniel on Tuesday, October 02, 2001 - 04:10 am: Edit

I put Seafoam in the crankcase last night. I thing the engine started to quiet down a little in the 7 miles it took me to get home. Also, this morning, the engine started much better without the "clicking valve" I had been hearing during cold starts. So, all in all, this stuff has done great. I'll pay attention to it for the next few days and see if it get's any better.

Thanks to all who responded
Daniel

By pk on Tuesday, October 02, 2001 - 10:34 am: Edit

It is the cam shaft end float. So very common in Discos. It won't hurt a thing. I had it fixed in my 96 and all is quiet; the dealer installed the button and it works. My 95 still knocks with the wandering cam. Won't hurt a thing except your feelings.

pk

By Bryan Crosby (Bcroz) on Tuesday, October 02, 2001 - 12:47 pm: Edit

Just curious PK, what did it cost to have the button installed?

bcroz