| Author | Message | ||
     flyor (Flyor) Member Username: Flyor Post Number: 45 Registered: 05-2003 |
There is always talk on here regarding sticking valves so I thought I would share my recent experiance with you. I currently have a 1998 Disco. I purchased this vehicle 8 months ago sight unseen off ebay with 94,000 miles on it. It now has 113,000 miles on it. This is my forth Land Rover. I've had another Disco and two RRCs in the past. I had an exhaust leak that I needed to repair before I go on a 3,000 mile trip. At first I just thought the flange on the y-pipe was cracked where it attaches to the manifold, but found that the left side manifold had a hairline crack in it. OK, I pulled the manifold off to get brazed up, I didn't know about the recall at the time. While under there I discovered some antifreeze that was leaking from between the block and head. I pulled both heads and sent them to my local machine shop to have the valves redone while they were off. Fortunatly I already had the new style exhaust valves. I had them soak the rocker assemblies in their tank to de-gunk them. I'm the third owner but it's looks like most of the oil changed were done. When I reassembled everything I replaced all the coolant hoses and the belt. So far it's running great. Total cost was $568.00. Some people on here wonder if this is something they should try at home. I have been a mechanic for 30 years, many of them were as a LR tech at a dealer so for me this job was no big deal. I've propbably done close to a hundred valve jobs on them. I would have done my own welding and machining but I don't work in a shop any longer so I had to farm that part of the job out. If your going to try it yourself make sure you have a clean, warm and lit place to do it. Have a good set of tools. You will have to be organized and clean. Have a proper repair manual. Take digital pictures if you need to. Take account of every fastener, one missing washer can ruin your whole day. Don't be in a hurry. No shortcuts. Try to have all your parts before you start the job. I delt with Dave at Alantic/British for my parts and he can help you out with what you may need. If you are in doubt in your machanical abilities I would suggest you support your local Land Rover tech and take your vehicle to him. Hope you found this either boring or informative. Cheers | ||
| Geoff 93 RRC (Geoff) Member Username: Geoff Post Number: 225 Registered: 11-2002 |
Very informative, thanks. | ||
| Randall Smith (Mr_smith) Member Username: Mr_smith Post Number: 215 Registered: 04-2003 |
Yeah thanks. It's interesting that you have owned 2 RRCs and 2 Discoverys. Based on erverthing you posted; I can tell that you are well suited to working on an engine. "Fortunatly I already had the new style exhaust valves." Do you fell fortunate because your ex valves are the "carbon cutter" type, or because they are the regular stemmed valves that you find on RRCs?? | ||
| Kevin Fedyk (Kovert) Member Username: Kovert Post Number: 103 Registered: 05-2003 |
I honestly don't doubt my skills as a abckyard mechanic. I am the best "direction follower"  . It's just now living temporarily in the N.VA in an apartment complex limits my area to work on a vehicle. They don't take too kindly to that. And know with the onset of a problem that is more and more sounding like a sticking valve, I'm getting nervous. | ||
| Phil (Discoanywhere) Member Username: Discoanywhere Post Number: 119 Registered: 06-2003 |
Very interesting... & inspiring! | ||
| flyor (Flyor) Member Username: Flyor Post Number: 47 Registered: 05-2003 |
Randall, mine had the carbon cutter valves. When I was still at the dealer these were the latest. They're almost $40.00 each. That's why I said fortunate. You have to pay close attention the the guide clearance too. | ||
| eric johnson (Eric2) Member Username: Eric2 Post Number: 240 Registered: 05-2003 |
flyor What, in your opinion, causes the valves to carbon up and stick? You would seem to have a better idea than most. | ||
| flyor (Flyor) Member Username: Flyor Post Number: 48 Registered: 05-2003 |
Eric. I would say alot of the ones I did were on Discos rather than Range Rovers, the same 4.0L engine. Most of the Discos were driven by "soccer moms". Start up, short trip. shut the engine off type. If driven harder they didn't seem to have the same problem. The dads were usually driving the Range Rovers and were more of in a hurry. I could be wrong but that was my impression. Personally I have driven my current Disco 19,000 mostly highway miles using the cheapest gas I could find and the valves didn't look too bad at all. Very little signs of carbon build up. It has a total of 113,000 miles now. The bottom line is I think the factory dropped the ball on valve stem to guide clearance. Again, too many pints. Does the Techron help? I used it in my previuos Rovers but not this one. | ||
| Randall Smith (Mr_smith) Member Username: Mr_smith Post Number: 218 Registered: 04-2003 |
Flyor Thanks for responding to our questions. The ex valve thing is a big issue with D1 owners. These guys need all the help they can get from having that expensive problem. What do you think the ex and intake valve to stem clearances should be?? Explain it any way you feel comfortable. Personally I have concluded that the program in the NAS GEMS system is what is really causing the carbon to build up on the ex valve. Using "carbon cutter" valves is just an attempt at treating the symptoms. Randall | ||
| eric johnson (Eric2) Member Username: Eric2 Post Number: 246 Registered: 05-2003 |
(Hi Randall) Flyor, Also in regards to the carbon problem, why do the 3.9's seem NOT to have the problem, IYO? Re: your comment about the factory dropping the ball on valve stem to guide clearance. I don't believe Rover uses top quality parts on their valve guides and valves as say, Toyota. Toy uses cast iron guides, chill hardened and then nitrides the valve stems. Would that have anything to do with the issue? Faster wear? Maybe that's not the problem. Your comment about the short trips is key. But lots of vehicles go thru that use cycle and don't seem to have the carbon problem. Then we're back to the valve clearance issue? I'm sure Toyota pays more attention to "non-critical" stuff like valve guide clearence. sarc/off | ||
| flyor (Flyor) Member Username: Flyor Post Number: 49 Registered: 05-2003 |
Eric, The 3.9L uses an EFI system called 14cux. It can't detect and record the misfires caused by the sticking valve. The GEMS system can as required by the EPA, which throws the "MIL" light on. I seen valves sticking on the earlier engines to the extent that it caused zero compression on the effected cylinder because the valve was stuck open. My personal opinion is guide clearance is a major contribution to the problem. Carbon just adds to it. Randell is correct in stating that the carbon cutting address a symptom. Carbon is a problem with many manufactures not just LR but if the guide clearance is too small the carbon just compounds the situation. I'm not an engineer, just a mechanic. These opinions are based on my personal experiance not scentific evedence. | ||
| Jaime Crusellas (Jaime) Member Username: Jaime Post Number: 239 Registered: 05-2003 |
Flyor, I don't need a valve job, but I want to be ready if/when I do. Did your local machine shop specialize in Land Rover, or could any machine shop do the valve job? I have the 4.0 engine overhaul manual, (just in case) so I'm sure it has all the specs necessary. I refuse to pay the dealer over 2 grand for a valve job. | ||
| flyor (Flyor) Member Username: Flyor Post Number: 50 Registered: 05-2003 |
Jaime, The shop I delt with has been around a least since I was a little kid. It's the only machine shop I ever took anything to that I couldn't do myself. I wouldn't say they "specialize" in LR but they have done them in the past. Dave, one of the owners, said that they used to work on these heads when Buick was still using that engine. The shop I use is in Roseville Michigan, IDJ. Any well equipped shop with a good reputation should be able to do the job for you. I would copy the pages of the manual and take them with you just incase. I would also start asking around for a good shop now, that way you'll be prepared in case you need them. If you want I can post the address and phone # to IDJ. | ||
| eric johnson (Eric2) Senior Member Username: Eric2 Post Number: 251 Registered: 05-2003 |
The shop I used for my rebuild has a motto" The standards of the (engine rebuild) industry are below standards". Go to the shop with the best reputation/most experience and pay a bit more. Not the more convienient shop that sells rebuilt short blocks for $599 and up. In those shops, the guy who was pulling parts and sweeping the floor 3 years ago is now assmbling your head. Probably no technical training, "Hey, any 'ol valve guide will work with any 'ol valve" - yeah, for about 10K miles. | ||
| Jaime Crusellas (Jaime) Member Username: Jaime Post Number: 240 Registered: 05-2003 |
Flyor, I guess if the guy at the shop you used remembered the heads when they were Buick, its a sign of a lot of experience!. I'm in NJ, so I'll take your advice, and keep my eyes and ears open for a good machine shop. I used a guy by the name of Tony Feil about 30 years ago to rebuild my 65 Pontiac GTO 389 heads. That car is still running! I should see if he is still in business. |
