SoCal420a submitted a new DSM Profile :

98 RS Long way to go.


Read more about this vehicle here...

so I finally got around to getting another engine, I picked a 420a for a good price, person I bought it from states it has about 150k, and may need head gasket, engine looks like a 420a with 150k that needs a head gasket, so will see hopefully it is not a pandoras box cituation, I am having a hard time finding a mech who can do help me check the 'new' engine and tell me what it might need be done, I dont have the real estate to break down an engine at the momet.

Well I can tell you without looking. If it has 150k, you'll want it bored .020" over and honed. Pistons to match the new cylinder size and rings. Crank polished and oversized rod bearings, maybe also main bearings. You may be able to skip on that but check it with a mic to be sure. Get the head pressure checked and surfaced. Get the block surfaced too if you're going to install an MLS gasket. Also get new injector o-rings. Engine fires are not fun.

A new water pump and oil pump is a good idea as well. New timing belt. New tensioner pulley. Use assembly lube on all the new bearings.

Need help, I'm here.

after a few weeks of looking for a 420a engine online or anywhere for that matter, I found someone 150 miles away willing to sell me their spare engine, it was abandoned in a shed with the oil pan out and and the bottom exposed and the top as well due to a pair of missing spark plugs, once I opened it i realize the cylinders and block had some rust, but the crankshaft is salvageable, I think I have enought parts on the purchased engine to rebuild my own engine.

Now with my engine out and taken apart, I am taking it to a machine shop to get everything straight and clean, I will update once I get my things bad to see how much they scraped off.

with my engine out of the car and taken apart, I can finally know the extend of the damage:
- 1 valve was hitting cyl 4
-that cyl rod bearing was loose
- cyl head has scrapes
-oil pan was so sunk in that it prevented the oil pickup to pull the oil properly, which I am guessing is where my issues started.





you can see the scratch in this pic, of the valve smacking the piston.

Hey guys, so I've made some progress on the engine rebuild, after a few setbacks, the head from me original engine (og eng) was destroyed by the machine shop, so I moved on to the head of engine I bough for spare parts (eng 2), and took it to a new machine shop, they did a good job, but turns out the head had some damage (see pic), the shop helped me locate a third head and I got that flat and clean. Trying to get the engine together, but I am having a difficult time finding the head dowel pins, one of the perks of rebuilding a 23 year old not so popular engine, dealers found 1 out in the east coast, but they don't know if it is actually in stock until the order is processed and they can have someone look and find it or not, and update the system, so that would put me 1/2 for pins I need, I ordered a pair from Mitsubishi Parts Warehouse (does any one have any feedback on them?), so fingers crossed they have it, and hopefully I wont get an email back from them in a few days stating they are cancelling my order since they are out of stock.

This shows the damage on spare head (eng 2), most of that wasn't completly visible until we shaved it. But luckly 2nd spare head was in great condition.

I've ordered a number of things from Mitsubishipartswarehouse.com before. I believe it's run by a dealership out of Florida?

Have you tried a Chrysler dealer for the dowel pins?

Salty-Seagull said:

I've ordered a number of things from Mitsubishipartswarehouse.com before. I believe it's run by a dealership out of Florida?

Have you tried a Chrysler dealer for the dowel pins?

Click to expand...

I finally got some dowel pins from them, but they werent the right size, I am guessing they stocked them as N/T but in actuality were Turb, so I ended up going to many machine shops around my area and just got whavetever matched the circumferance, I had to machine off to right length and presto.

Car is finally running, after a long long time working weekends on it, engine and trans seem be running good. Haven't had a chance to drive it on the freeway.

I have one minor issue so far, the fan doesn't turn on until the temp gage registers around 75-80%, and when the fans kicked in, the temp goes back down to 50%, this is the first time i run proper thermostat on the car, so I don't know if that is normal, I put a new temp sensor, I hope it didnt get one for the turbo engine and that is what is causing the misread.

My stock temp gauge never reads above halfway. There's definitely an issue somewhere.

Hey everyone, so I finally got it going, last week, passed smog (CA) on the first attempt, paid a ton for renewal since I never put car on non-op, you would think i learned my lesson from the previous cars I did the same. But alas it is officially registered. New engine feels nice, although I only have about 250 miles on it, new started just came in, will work on that in the coming days, and everything else in the car needs replacement, fixing or deep cleaned, so I will keep posted here. For whomever is watching.


Things that definitely need immediate attention: brakes, suspension, alignment, weather stripping all around. Car sat for 8 years, so everything is rusted or shut to hell.

BLACK'98DSM said:

Well I can tell you without looking. If it has 150k, you'll want it bored .020" over and honed. Pistons to match the new cylinder size and rings. Crank polished and oversized rod bearings, maybe also main bearings. You may be able to skip on that but check it with a mic to be sure. Get the head pressure checked and surfaced. Get the block surfaced too if you're going to install an MLS gasket. Also get new injector o-rings. Engine fires are not fun.

A new water pump and oil pump is a good idea as well. New timing belt. New tensioner pulley. Use assembly lube on all the new bearings.

Need help, I'm here.

Click to expand...

I literally did all of the above. Engine in break in period now, everything seems to be working ok, passed CA smog. Thanks for the input, greatly appreciated.