Low compression, rough idle, loosing oil, where to get a crate 420a engine

[shaggy19953]

So my vehicle just got it's timing belt changed 10k ago. Ever since then the car has been idling rough. I can turn it on, and it runs fine for the first 10-20 seconds, and then the idle gets a bit rough. Not enough to cause the engine to jerk or cut off. It's not throwing any codes either. I assumed that durring the course of changing my timing belt (jacking up the motor) i may have disconnected some wire or vacuum hose. The car drives fine, acceleration is ok (from the best i can remember) and fuel economy is great at 32-38 highway.

So, i decided to check my compression yesterday. The numbers are 210, 190, 210, 214. After a quick look in the haynes manual it stated that if on cylinder is 20% off and has a slightly rough idle, that one of the exhaust lobes on the cam may be worn. While i suppose this is a posiability, I find it hard to believe that it just started the day i finished my timing belt. I was unable to put oil in the cylinder because i forgot to get an oil can. Silly me also forgot to prop my throtle wide open, should that make a huge difference ?

Also, right around oil change time, the oil light comes on. Normally only durring hard right hand turns. So obviously I'm loosing oil somewhere.

The engine has 151k on it, and it gets driven 120 miles per day (round trip) all highway. Obviously i'd like my vehicles to live as long as possiable with this kind of travel.

Now for the last question, i promise. Where would one find a good crate motor for a 420a ? I know i can rebuild it, and i know i can buy rebuilt. But, i'd just prefer something new. I'm sure it's going to cost my some money, but i need some sort of warranty with this kind of driving. I've seen a few places online to buy new but not sure which is the best. Finding a new motor with a little extra HP wouldn't be bad either.


Thanx in advance..

-=<> Aaron <>=-

 

[BLACKpsiECLIPSE]

Check ebay, they always have that stuff.

 

[Locke]

so ever since you changed the timing belt it has idled rough? are you sure the cams are aligned properly? and yes, you ought to have the throttle wide open while performing a compression test. you also should pay attention to how quickly it builds pressure, not just how high.

You can use a tea spoon to put oil into the cylinder. And with 151k miles, I wouldnt expect the engine to get ~210psi. Carbon deposits perhaps. If so, MCCC is good stuff.

Howell Automotive has good engines, though they are race engines. (http://www.howellautomotive.com). If you want new, maybe Satan or Chrysler sells them crate.

Although, IMO, for what little seems to be wrong, i would, personally, spend my money repairing the motor you have. A vacuum test would help determine if that 190psi cyl is a valve problem, and looking around the motor may show you where oil is leaking from.

Regardless of what you do, I hope you get your problems taken care of.

 

[dr1665]

Sounds like either your timing is off a hair or your CLT sensor has shit the bed. Can't hurt to try replacing the CLT since it's only $25 or so and you've got some serious miles on that bad boy. If that doesn't help, might as well bite the bullet and double check the timing belt.

Idle problems coming right after a timing belt job are almost always timing-related.

 

[shaggy19953]

Well, right after I replaced the timing belt we tried to run the car. That time we obviously were off 1 tooth. The car threw and engine code before i even left the driveway. I had someone else (father in law) fix my failed timing belt attempt. They re-did my job and found the idle problem. So, they finally pulled it apart the next day to no availl. I'd hate to rip that thing apart yet again. Maybe it's time for it to go to the shop. If the timing was off, would I still be getting decent compression ?

Howell automotive i have checked, and while a stroker sounds nice, no warranty doesn't. But thanks for the link anyway.

CLT sensor ? From all i've found online that's a coolant temp sensor. How would that effect the idle ? The temp guage reads fine, just like it always has.

The pressure built up relatively fast on all cylinders. I can't recall exactly how many psi per compression, but it took 6-7 stokes to get it to max out.

Any "good" rebuild kits i should be looking at ?? I'd have my mechanic do any of that work, as I don't have the time nor space to attempt it myself.


Thanks again.
-=<> Aaron <>=-

 

[95burgundyesi]

overbore.com you can get the brand spankin new 420a or 4g63 haha if ## up for it

 

[Blitzeclips]

Those are good numbers for compression for sure.

If you want to rebuild you should check out some vendors with the available pistons, rods, etc...

You are in delaware, AWESOME.

What shop did you take it to? Or, where does your father in law work?

 

[shaggy19953]

Overbore.com.. looks pretty good, and with a warranty, awesome.

As far as where i took my car, it was just a little hole in the wall. My father in law know a bunch of people in low places if ya know what i mean. As far as getting vehicle work in delaware (i live in kent county) I visit World Transmission. Don't let the name fool you, they do everything. The owner runs race boats, so he works on them too. The guys name is Tom, i've been going to him for years, and would trust him with any of my vehicles. Another good place to go is Rose's engine shop.. They are on rt 13 north dover, across the street from Lowes (more or less) I've not been there, but i've heard nothing but good about him. He actually talked me out of buying a cat. converter for my old chevy.. He could just as easly sold it too me, knowing it wasn't going to fix my problem.


Thanx for the replys
-=<> Aaron <>=-

 

[Shadow98]

You can order a rebuilt engine from autozone and it comes with a 3 year warranty. They spin test the engine to make sure everything works fine before they ship it. Don't recall the price, but it's around $1500.

 

[shaggy19953]

Yeah, i know Autozone and advance sell remans.. I appreciate the input, but i'll pass.. My brother in law just got a chevy 350 from them about two years ago.. A year after he got it, something took a nose dive (oil pump i think) and his journals were completely trashed.. I think they did give him a new engine, but he still had to take a couple of days to pull out the old one, and put in a new one. I on the other hand would have to pay someone to do the swap. I've bought a bunch of reman products, and i've only had a few they didn't die pretty soon after..


-=<> Aaron <>=-