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how's about the 3.9l?

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frankenstang57

frankenstang57

Jedi Warrior
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Question for you guys. I have a Stag with a crappy Buick motor in it. I'd like to swap it for something else. A 302 was my first thought, but the front mounted oil pump kinda bugs me. Locally I've found 2 3.9's in Land Rovers. One is a '91 and the other is an '89 and of unknown mileage. Are these motors worth a darn? Any tell tail signs to run the other way? Do they still use some sort of GM bolt pattern on the bell housing? Thanx!
 
From what I can gather, the 3.9 seems to be good. It produces 178hp (should be enough) and the only problem that I can find is as follows:-

Hard starting: Difficult starting or a no-start is probably due to a bad ignition coil which has overheated. (The pitch may have even leaked out.) The ignition module is the root cause. (1992-94)

Couldn't find anyting specific to a '91 or earlier. Biggest concern, of course, is how the motor was treated previously. If it's a good 'un then you should be fine. Look for evidence of oil leaks, as there was a problem with rocker cover gaskets at one point.
 
i have a nology ignition system in my rangie, never a problem starting. even if left sitting for a week. No leaks. I had to rebuild the heads, replace the waterpump and radiatior. and I had a problem with the temperature sensor telling me it was running hotter than it was. However, I did drive it from san diego to eugene oregon when i bought it with a blown head gasket (in the summer to boot). and i have found the engine easy to work on and parts easily available. xjs jaguar (a sponsoring vendor) is a good source for parts.

The beat up old rangie has turned out to be the most reliable car I own.
 
Keep in mind some aluminum motors corrode internally,if the anti freeze has been neglected. This engine is lightweight, so it wouldnt make a MGB noseheavy.
 
I could go on & on about the Rover motor, but the two most important things about them were, they can exhibit a bad head gasket, when in fact the steel sleeve in the cyl block slips & cause compression of the cooling system. Ask me how I know...They are expensive motors to do machine work on. I thought I heard something about the 3.9 late 90's disco motors have some valve issue, but I was running a '88 3.5.

Try this link: Talk to Woody, he is a big time TR8-Rover motor guy..

https://www.thewedgeshop.com/
 
I think in the mid 90s they changed from a 5-bolt head pattern per cylinder to a 4 bolt one as this tended to "bow" the head less.
Smokey Yunick once said "It takes a pound of aluminum to equal a pound of cast iron."
 
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