I just bought a '92 expo and the motor started to knock and I'm wondering what motors will just bolt right in without any major issues. Its a 2.4 sohc 8 valve auto. It wouldn't pass the emission test, high nox. reading, it was sucking air in at the injecter bases so I replaced the Orings under them and it started to run better so I drove it a few miles an the knocking started. Its a loud one like a rod or wrist pin, it needs to come out. I read on the net of 6 bolt and 7 bolt motors. What would mine be? Any tips on the swap will be a big help. Thanks

 

When was the car built? pre 92.5 had 6 bolts after 92.5 had 7 bolts.

 

I went to the Mit. dealer here in town and the parts man said he couldn't find a build date on his computer. He told me to look on the door sill. Oct. '91 is printed on the sticker so I assume its a 6 bolt. does that mean the only motors that will fit old '92.5 and before motors? I see on the net some hyundais have 4G64 motors. Are they 7 bolt motors after '92.5? If the temp. stays out of the 90s for a few days I'll have a chance to yank it out and see just what I need. Maybe I just need to fix this one. I'll be back with more details of this project.

 

Ok, I yanked the motor and it looks like its a recent rebuild. You can see the cross hatch from a recent hone job. It had blown a head gasket between 3 & 4. I'm still pressure washing on it so I haven't droped the pan to check on the knocking sound it was making, it may have been just bad detonation. I've found things wrong with this motor, it is leaking alot of oil andthe intake gasket wasn't on rightso it was sucking in fresh air at #3 & 4along with leaking injector bases to make it run bad but it was so covered in oil at the belt end I can't tell where it is leaking. I still can't tell whether its a 6or 7 bolt motor? What'sthe differance?There are 6 bolts holding on the flex plate! Theres only 4 bolts at the bell housing, the lower 2 are about 12ins. apart and the top 2 are about 4.25 apart. I'm going to fix this one but i'd still like to know. I just hope I can get this one back in, man what a fight getting it out, its a tight fit. I'll let ya'll know what I find when I pull the pan.

 

You have a 6 bolt, its how many bolts are on the flywheel/flexplate. Drop the pan and check for metal.

 

Pulled the pan, no metal shavings. Pulled the caps off 3 & 4, they looked good,(min.ware). The knockingmust have beenbad detonation. The balance shafts are gone, lazy rebuilders? How will that effect the way it runs. It ran but ran poorly when I bought it, drove it 30 mis. to get it home! This motor should run for yrs. with all the new parts that are in itbut will it vibrate itself to death soon with no shafts in it? Should I continue witha swap or will I be ok with this motor? This is my 1st mitsubishi, its just going to be a work van but I don't want to be chasing endless problems because of this motor. I appreciate and look forward to your feedback. Thanks

 

they took the balance shafts out because they are prone to breaking, they're not necessary but you will feel the extra vibrations.

 

I've been working on the head so I can get this thing back together and found a .005 warp in it, its lower in the center. It took about .014 to clean it up. This heads been through HELL! Weld around 1,2,& 4 intake valve seats and weld in 2 & 3 intake ports, new intake seats in 2 & 3. It looks like the repairs are good though. I'm a machinist so I'm giving it a light valve job since its off. Cleaning off the old gaskets and the black RTV has kept me busy. They goobed it on everything! I'm using NAPA aviation Form-A-Gasket sparingly on most gaskets. Its not going to leak oil when its back together. I'll be back with more.

 

Post pics of your build.

 

OK, so I put the motor back in, took all day and I learned alot. The next day I hooked everything back up and started filling it with coolent and it started leaking out around the pump somewhere. I couldn't see where, too much stuff in the way. I couldn't believe it. I had it off, cleaned it , and put a new gasket on it when I had the motor out.I wanted to know ifit would run so I hit the key and it fired right up. That made me feel better and I figuredI;d find the leak the next day. I started filling it today to see whereit was leaking from but it didn't! I had pulled the belt and undid the motor mount so I could see and not a drop! I put it back together, the radiator was full now so I started it up and searched for leaks but it stayed dry and now coolent up at the sending unit so the idle came down as it warmed up and it was running fine. All I can think is the pump needed to spin to make the seals work again. I drove it around some today and it seem run good enough to pass the emission inspection so I'll take it in tomorrow for that and let you know how it goes. I took some pictures, of the head after I faced it, the end case where they pluged the holes where the shafts had been, and the engine being set in with the hoist but I don't know how to postthem. I sure am glad this repair is over but I'll be alot better at something like this next time, I learn alot.