420A ? About doing a compression test

screwlegg · Jan 27, 2018

I got a 420A Eclipse that the timing belt slipped about a year ago and already put the belt spot on to the best of my knowledge. I'm just now getting around to working on it.

I'm trying to do a compression test on it tomorrow I just need to know if the car "HAS" to be at operating temperature because my car won't start it just tries to start and when I'm testing the cylinders do I take all spark plugs out or just test each cylinder one at a time and put the plug back in

Brembo · Jan 27, 2018

It don't have to be at operating temperature. If the car don't run then you can't have operating temperature. Just make sure that you have the same compression from cylinder to cylinder. If one is low then you found your problem. Good luck. Post results.

screwlegg · Jan 27, 2018

Thanks Brembo for getting back to me so fast I guess that was a stupid question but it's better to know than not... Just one more thing does it matter about the spark plugs like I was saying in the 2nd question? Sorry just never really messed with an engine before and I don't want to open up the head if I don't need to for something I messed up on!

motomattx · Jan 27, 2018

Take them all out, it will spin easier.

screwlegg · Jan 27, 2018

Thank you, thank you... I will post results in the AM y'all helped a lot

pauleyman · Jan 28, 2018

You slipped a belt but didn't change the head? Are you trying to check and see if you have bent valves?

motomattx · Jan 28, 2018

Some of the Chrysler based 420a type are non interferance.

screwlegg · Jan 28, 2018

Yea just trying to check if the valves are bent before I open her up who knows maybe it's not the valves so o just want to check first. It's a interference engine, I didn't get to doing the test today but maybe tonight or tomorrow because I have work

chrysler kid · Jan 28, 2018

motomattx said:
Some of the Chrysler based 420a type are non interferance.

Haha

No

screwlegg · Jan 28, 2018

Just did a comp test and did it twice this is what it read

1-100/100
2-150/140
3-30/40
4-60/80

motomattx · Jan 28, 2018

chrysler kid said:
Haha

No

YES! the 2.4 is non interferance, so depending on what block that car has in it, it can be non interference.

screwlegg · Jan 28, 2018

motomattx said:
YES! the 2.4 is non interferance, so depending on what block that car has in it, it can be non interference.

No need for disputing over something so silly not what I intended of this thread. But max do u know of any guides for removing a head if not a place where I can get a shop manual as thier is no dealers close by me

chrysler kid · Jan 28, 2018

motomattx said:
YES! the 2.4 is non interferance, so depending on what block that car has in it, it can be non interference.

Oh, must have missed that one in the factory service manual.

chrysler kid · Jan 28, 2018

screwlegg said:
No need for disputing over something so silly not what I intended of this thread. But max do u know of any guides for removing a head if not a place where I can get a shop manual as thier is no dealers close by me

The best value is to buy a set of factory service manuals for a 97 eagle talon on eBay. I got a good set for $10 shipped on eBay, that's the service manual and electrical manual

Also keep an eye on Craigslist for a used motor from a junkyard car with a warranty. The 420a motor should be easier to find as a full yard pull, where as the 4g63 is alot less common to find in a regular junk yard

motomattx · Jan 28, 2018

What I'm getting at is that its not uncommon for a 20 year old 4cyl car to have had the original 420a swapped for a 2.4 from a cloud car by now, there are several just in my small neighborhood that have been.

The Top DSM Community on the Web

420A ? About doing a compression test

screwlegg

Brembo

screwlegg

motomattx

screwlegg

pauleyman

motomattx

screwlegg

chrysler kid

screwlegg

motomattx

screwlegg

chrysler kid

chrysler kid

motomattx

Similar threads

Latest posts

Build Thread Updates

Vendor Updates

Latest Classifieds