Tawàyama Safaris - 4.2l Virtual Rebuild

2/14/04 - Valentines Day. How appropriate is it that I start my rebuild project today? Maybe I shouldn't worry about it and make sure that I get Polla some roses and a card and just start the engine project anyway. Hehe.

I guess the object of this 'rebuild' is to increase my skills a bit and really dive into an engine and figure out just how it works. I've never tackled anything like this before, so I need to clarify at the start that I am NOT an expert mechanic, and am really doing this by the seat of my pants, using some factory manuals and relying on friends both on the phone and advice and guidance from the internet. I hope that the reader doesn't think that I 'know it all' in regards to engines, quite the opposite. The reason I'm doing this is so I can learn how to service the motor, how to fix what will go wrong, and to broaden my general knowlege of vehicles and how they work.

The engine that I'm starting with is a Rover 4.2l V8 which was in my 1990 Range Rover up until last fall. I blew the head gaskets due to a faulty temp guage, and rather than fix the engine and run the truck, I decided to part out the truck and sell the engine. Well...my potential buyer of the engine fell through, so I was back to having this motor to deal with. I'm kind of excited (aside from a potential sale) to have it back and learn a thing or two. The 4.2 was a longblock that I bought from Mike Smith of East Coast Rovers several years ago when the 3.9 that was in my Range Rover broke the timing gear and toasted the motor. I purchased the short block from ECR, and had it gone through and totally rebuilt. At the time the head gaskets blew it had roughly 60K miles on it after the rebuild. Prior to the rebuild I believe Mike Smith said it was a low-mileage 4.2 out of an LWB they put a Pursuit motor in (higher performance, mucho higher $$$$).

So, the goal is to obviously fix the blown head gaskets, put on some Buick 300 heads, new cam, new waterpump, rebuild the oil pump, and have a good motor ready to go when and if the 4.2 in my current LWB has any problems. I hope to document in a way that is easy to follow the progress and decisions (and problems) I encounter while doing this project. Any feedback is much appreciated, and please if you see something I'm doing wrong, don't be afraid to e-mail me.

Thank you.

Michael Slade

2/15/04 - Found out today my Buick heads aren't coming. I was too slow and they were sold before I could aquire them. You snooze you lose! Now I'm kind of looking for another pair...know of any?

2/23/04 - It's been a while but today I spent about 3 hours and cleaned it up. Got the starter off (8mm allen bolts), got the oil cooler adapter off and cleaned up and pulled off one of the rocker covers. Got the valley gasket off too and cleaned up the galley and rinsed some guck down into the pan (at least I think that's where it's going to end up). Also removed a bunch of random ground straps and the power leads to the starter. Took off the engine lifting bracket, cataloged all nuts and bolts in ziploc bags.

Jim Pendelton said I ought to go ahead and pull the heads, so I pulled out my Defender shop manual to see how they do it. The order they show in the manual is to remove the timing gear cover, remove the timing gears, cam and THEN you can remove the heads.

I didn't know if you needed to remove all of that stuff to pull the heads, or if there was a more logical order, so until I get some feedback I'll probably let it sit for a while longer. I stopped with the removal of one of the rocker covers, put a bag on the engine and wheeled it back in.

That's all for today.

Bosch Platinum plugs as they came out of the engine. I think these have about 30-40K on them. The starter cleaned up nice, and it's original to the 1990 Range Rover I originally had the motor in. The starter has 255K on it and was working fine when I pulled it out. It'll be good to have a spare for the other Range Rover. Once the engine was cleaned up it didn't look all that bad.