3.0L Mits engine swap

I have an 87 1/2 Caravan with one of the very first 3.0L Mitsubishi engines. At 130K highway miles I have finally been bit by the slipping exhaust valve guide gremlin. I'm off the line like a fully loaded cement mixer but can maintain 60 MPH on the flat, more downhill when I get going! Now it's parked and I must make repairs. NO smoke out the tail pipe. I have already been bit by the harmonic balancer removing the key and keyway from the crank. I had to machine a colet to hold the balancer on the crank. (it may never come off) The van looks NEW Great paint perfect inside always garaged so I think it's worth a DIY repair. It seems this engine had many faults the first few years then was a real winner. The punchline is if I wanted to swap the entire engine with say a 96-2000 engine what problems would I have? My dad has a 97 Caravan and I was looking it over and his 3.0L looks the same. Except the intake plenum is a little lower for hood clearance. So I may try and find a 3.0L from a salvalge yard.

From what I can see if I use my 87 throttle body on a newer engine the

old computer should work fine. I only question the fuel injector wiring / interface though. I have all the factory shop manuals and the pull is out the hood on these early models. Soooo it seems to me the entire engine swap may be a lot less trouble than replacing the heads plus I can change the timing belt on the new engine before I install it. Anyone done this before? Will this job require me to purchase a $50.00 bottle of Tequila about 1/2 way through? Or should I just opt for a set of newer heads? It sure looks easy to pull the entire thing out and pop a newer one in. Thanks, Bill

Reply to
N5ZTW
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Even if the nuts and bolts between engines all match up there could be issues with different flavors of computers, sensors, fuel delivery systems, etc. Be careful in your selection.

Reply to
Steve Stone

Reply to
N5ZTW

A few years ago my brother and I put the engine and transmission from a

1988 caravan into a 1990 caravan (both 3.0L). There were a few differences in the throttle body and related parts as well as a couple of other things I don't entirely remember. In all cases when something didn't match, we simply used the part that matched the van I was going to be driving. I'm pretty sure that the basic engine is the same under all the accessories. In the end this was a very dependable vehicle with no problems. This was the opposite of what you plan to do. I put an older engine into a newer van.

If something doesn't look right, maybe you should stick with an engine closer to the correct year. There may not be any problems at all with the engines that are ten years off, but I would feel more comfortable not going past 1990. One of those years around 1990 the computer was changed to a newer model with twice as many wires. You can look at vans in the junkyard to see when they changed.

N5ZTW wrote:

Reply to
Robbie and Laura Reynolds

Reply to
N5ZTW

The basic short block (block, heads, etc) are the same. Just put your accessories and intake on the new motor, and your set.

I would recommend getting a 94 or newer motor, as they had the most updates to the heads.. (IIRC).

If you get a junkyard motor, it might be a good idea to freshen it up a bit. New rings and bearings, valve job (with maybe a 30-32 degree backcut on the valves for a little extra flow), and new gaskets.... even if you dont want to do rings and bearings, at least replace all the gaskets...... save yourself a future headache...

Also put on a new timing belt and pulleys, water pump, water transfer tube, and any other thing that is harder than hell to do with the motor in the van.

Of course, you could always just drop it in, put your stuff on it and GO!

Reply to
Homer Simpson

...and cross your fingers!

Reply to
DeserTBoB

Thanks for the info. I'm in Austin Texas and there seem to be many of these around. I found a 97 listed at a local bone yard as "fire on top" I'm going to go look at it and see how bad the fire was seeing I'm going to replace the intake system anyways. But a fire on an engine with Alum. heads could be trouble. Just worried that it may have debris in the combustion chambers. Stuff that won't come out like melted plastic that fell down the cross flow path into the intake ports. In the past I have used a shop vac in the spark plug hole for this kind of issue. They also have a 98 but it was hit in the front so I have to go look at it also. One question is will my 87 optical pick-up distributor drop into the newer engine (valve train). I think I will need do this to make the

87 computer work as I'm sure they must have changed them > The basic short block (block, heads, etc) are the same. Just put your
Reply to
N5ZTW

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