Dang stupid AMC 401

[243]

A few of you know I have been pretty set on swapping a sbc into my Cherokee. I started the listing on Ebay tonight and decided I better pull a head and check to see if it was bored when my Grandmother had it rebuilt...you know at least one bidder would ask me to verify it, right?

You may also remember that I couldn't pass low idle emissions and the #3 spark plug would barely fire.
So I pulled the drivers side head because the #1 and #3 cylinders had low (80 psi) compression.

There were no marks on the pistons but I decided to mike the bore. I'll be danged, the #1 cylinder is 4.165" at mid-bore, in the 9-3 position. Cylinder #1, #3 and #5 were glass smooth with no visible scoring and had almost no ridge. It appears that they just re-ringed.

Keep or sell???

I know that's a silly stupid question to ask a bunch of Jeep guy's but I want to hear what you have to say. I know small block chevys backwards and forwards and they are a lot cheaper, I can use the single serpentine belt system, get shorty headers yada yada yada....

......AAArrrrrrrrgggghhh!!!! why couldn't it have been overbored so I could be at peace with myself smile.gif

Why did I have low compression?

[jeepguzzi]

Maybe a bad valve grind or a weak valve spring.

[243]

guzzi~

Yer saying that a bad exhaust valve will let the air out on the compression stroke???

[joe]

As much as I love Jeeps, AMC I-6's and the Buick motors Kaiser used in the past there'd be no hesitation on my part to dump any AMC 304/360/401 into the 'soon to be cast iron cookware pile' and go with a SBC. Sell it to a believer and then buy what you really want...I won't tell. ;)
Thought I'd better vote early since you're prolly about to be overwhelmed by the AMC 360/401 true believers. :D

[joe]

Originally posted by 243:
guzzi~

Yer saying that a bad exhaust valve will let the air out on the compression stroke???Yup, that's what he's saying. Squirt a couple tablespoons of oil in there and re-do the comp test. If the readings come up the oil rings are bad. If not the valves are.

[gsmikie]

treat like a jag.......... sell it while its still running

[FSJeeper]

Compared to other engines, the AMC V-8 is a POS. Ditch it and get a GM. Better yet a GM diesel.

[JeepBountyHunter]

Hey what's the listing number???

[Rande]

The oil rings don't help with compression. The oil-in-the-cylinder test is for the compression rings.

[TEX]

If you sell the 401 give me the first shot of getting it off of you. to help you out a little, go with the 350. waaaayyy better mod capabilities and way cheeper to upgrade.

Thanks

TEX

[joe]

Originally posted by Rande:
The oil rings don't help with compression. The oil-in-the-cylinder test is for the compression rings.Opps...yup your right. smile.gif

[243]

chief~

I was through with the description and filling in the listing price when I decided to go out and pull the head so it didn't actually make Ebay.