Engine rebuild......

[CJim7]

i havent researched this yet in my local area, but what roughly can i expect to pay for an engine rebuild on a 401?
Figureing line bore, cylinder bore/new pistons (possibly), new cam, turned crank, and all the usual goodies that goes with the block.
Also reworking the heads.
I know regionally, prices vary, but i know what to expect for a 6cyl rebuild....what am i looking at for a V8?

Would i be cutting a noticeable chunk out of that bill by doing a good portion of the reassembly myself (everything but crank, cam, and timing set install)?

Somebody i work with said he had a SBC built here in the area and it ran him $3200 :shock: I dont know the particulars other then a high-end valvetrain, but that sounds a bit high to me. :-|

[jeep_man_401]

I think $3200 for a AMC good rebuild with all the machining (bores, decking the block, crank plus cam bearing install) would be a steal.

Bowties are alot cheaper to build...although I could be wrong. Check Gopher http://www.gopherengines.com/index.html rebuilds or go to napa and look around. Otherwise I think you're in it for $4000 plus for a good rebuild with new parts.

My 2 cents

[tufcj]

I did the assembly on my 390 myself. I had it bored, balanced, crank cut .010/.010, heads (291C) done with hardened seats, 3 angle valve job and mild porting, rods re-sized and ARP bolts installed.

Parts I bought were forged pistons (Ross), Crower cam and install kit, Crane roller rockers, stainless valves, Milodon crank and head stud kits, and a full Felpro gasket kit, crank and cam bearings, rings, etc.

Total at the machine shop was about $1400, about $1600 in parts, so it ran just a little over $3K for everything.

Bob
tufcj

[tarior]

The last AMC I did (360) cost me about $1400 for parts and machine work, I did most of my own assembly. That was a few years ago, but I don't think costs have tripled.

[1980_Cj7]

Just rebuilt the same 401, twice in 10 months, using two differnt machine shops. Both times the machine work alone was $2100 to $2200. Parts were about $1700 with forged pistons, about $1500 with hypereutectics. So, bottom line was $3700 to $3900 roughly. (I don't have all the receipts in front of me and am going from memory, but I think I'm pretty close.)

[zero cool]

I had my 401 rebuilt a year ago. I took the complete block to the shop. I got back an assembled short block with new pistons, turned crank, new bearings all around, etc. The heads were fully rebuilt with new valves, springs, etc. Cost me just over $2K.

I assembled the rest of it.

[1980_Cj7]

I had my 401 rebuilt a year ago. I took the complete block to the shop. I got back an assembled short block with new pistons, turned crank, new bearings all around, etc. The heads were fully rebuilt with new valves, springs, etc. Cost me just over $2K.

I assembled the rest of it.

Did the $2K include machine work, parts, and assembly? If so, that's a super deal!

[Mcktiger74cj5]

i just did a 360 swap in my cj5 total machine work/short block 1800.00 new pistons finished motor 3000.00

[CJim7]

Jebus H.....im going to have to sell 2 of the 3 kids on Ebay and pimp the wife out to afford this :shock:
If i can keep this around or under $2500...i think i'll be happy.
Anything more then that and i think i can get a brand new engine :roll:

[82Waggy]

Depends on what you call a re-build.


If you can get away without having to purchase new pistons and just deglaze the bores, re-ring, and surface the decks and heads, valve job, gasket set, bearings, etc, maybe a cam w/lifters and roller chain, then you can probably refresh what you have at nearer to or less than $2k.

A complete rebuild with all new parts and pistons, basic machine work and balancing, 4bbl mani with carb, water pump, oil pump, etc. can easily push $4k or better.

Start adding performance parts, setting zero decks, a full blueprinted machine job and headwork, and things can get expensive in a hurry. I have right at 10k in my 401MPEFI motor with all new parts including headers and starter - the only thing re-used was the core block, crank, and rods.

[tarior]

Heck, an Edelbrock EFI and set of Edelbrock heads are about $4000.

Just a refresh should be well under $1000, so long as you don't need all new valves. Considering you can do your own assembly work, of course.

[82Waggy]

I used stock heads on my 401 and did the assembly myself.

Don't know how you could do a refresh of any merit for a grand.

Valve job, surface, and seals will cost over $200 by itself if no new valves or springs are needed. Probably need new cam w/lifters and springs too - another couple of hundered or so.

It just keeps piling on

[tarior]

Recondition heads ~ $200
Have crank turned includes bearings ~$200
Tank the block $50
Gaskets and rings ~ $300
Oil and water pumps ~ $100
Freeze plugs ~ $35
Cam bearings, installed ~ $100
That's $985.
That leaves ball honing, checking parts and clearances and all assembly to the owner. I also assume that the valve guides/seats aren't destroyed, and I'm sure it wouldn't come close on a race engine.

[82Waggy]

Where is the new cam, lifters, valve springs, main and rod bearings, rockers, timing chain set, carb overhaul - all worn items that should be replaced as part of a rebuild.

Close, though, if you do not need new pistons, decking, head surface, boring and hone, hardened exh valve seats (which you probably need if it is going to last any significant milage).

Change piston types and you should add balancing the rotating assembly. And you could improve combustion efficiency and mileage by improving quench. Hows that timing cover holding up? Are the rods still true or do they need to be resized? Dizzy ok or just replace it? Might as well stick a performer manifold and new 4bbl on there while were at it for just a little more money. Those old exh manifolds look pretty tired - throw on some new headers.

Repair the junk with losse old pistons or make it right. Just depends.

[tarior]

The mains and rods come with the crank being turned, at least at my shop. With a freshen up, the cam, lifters and rockers go back in, I did forget about the timing set, though. :oops:

[jeep_man_401]

I think everybody here is saying if u can get a $3200 rebuild (done right) you should jump on it.

I did a 360AMC back in high school for about $3000 but it got a reground cam (Berry racing) stock pistons (9.5 to on cast) cheapy rings, stock timing cover and gears (before the Internet!! sorry MC) bored .030 over got new guides and a couple valves, reused the stock valve train. Had it balanced though.

I turned it 6000rpm all the time, only broke 1 rocker bridge and bent a push rod and took out the lifter. It dynoed 232hp at the rear wheels.

I now have sunk $8000 plus into a 401 the dynoed 460hp at the flywheel at 5500RPM...has roller rockers KB pistons, total seal rings, Indy heads...You get the picture. This motor was made to build onto, have alot more power to make in it yet. (where are the 2" headers for these motors!????)

Chevy's are cheap and good for higher rpm.

AMC's have a good hard block (ridge reams where made for chevy's!) and good flowing stock heads. Don't be afraid of 2 bolt mains either! Compare bolt sizes to a chevy!

If you want to compete against the Chevy's you have to spend more. It's not that one is better than the other, just parts are higher for the AMC's. A sad fact of life, but they are getting more and more attention. When I built the 360, alum. heads where a pipe dream for the AMC's.

It may be cheaper to put a Chevy into a Jeep, but in my opinion, it's not Jeep no more.

I suppose some cost comes down to the machine shops also, location? In the "sticks" local old guy, probably a damn good deal. Big town, "race shop" guy...premium prices.

Step up to the plate and build you a good AMC motor and you will never regret it.

[tarior]

I think everybody here is saying if u can get a $3200 rebuild (done right) you should jump on it....

....Step up to the plate and build you a good AMC motor and you will never regret it.

Can't argue with that! :sa:

[CJim7]

Thanks for all the insight guys.
Everybody around here keeps asking me why i dont just drop a SBC in it or find another 258 :roll: . I've been dreaming about haveing a 401 since i first bought this jeep 15 years ago......so im not giving up on it now. :wink:

Im going to have this done right, for the most part, i'll stick with stock parts however, might go with a Summit kit for the cam. Already useing a Performer intake. Gonna stay with stock exhaust and im not looking for any P&P on the heads. Might get one of them fancy schmancy Bulltear timing covers i hear about :t:
I'd love to get this engine around 10:1 compression for the simple fact i want to run propane at some point, but that may just be big dreamin right now.

I think the plan now is to get the engine out of the Jeep and continue the teardown. i'll research shops around here and see what sort of "gut feeling" i get from talking to them. This may be a long drawn-out deal so i'll probably pick up a local cheap 258 and drop it in the CJ so i can at least drive it around. That will allow me to take my time on the 401 and not get into a rush because of Jeep withdrawals. :razz:

Thanks again. If anyone has anything else to add....id sure love to hear it.

[tarior]

Stay away from the Summit cam.
I would go with a Comp 268H or similar.

[82Waggy]

I would not use a Summit cam either.

Here is a list of everything I did to my 401.

http://www.bulltear.com/forums/viewtopic.php?t=6690

Might help you to organize your project - you can add/delete your own configuration.

If you a not going to run propane right off the bat, I would hold compression to no more than 9.5:1 on premium pump gas, preferably closer to 9:1.

[Goose]

I have been reading along and I think there is one small detail that has been overlooked.. the question that needs defining is this: when you say "rebuild" do you mean REBUILD?? or overhaul it seems like those two words get used interchangeably.. heres the definition.. to "overhaul" is to replace wear items.. service parts.. rings, bearings and gaskets cam and lifters if needed.. hone/ deglaze cylinders (they usually arent that badly egged) go through the heads and regrind the valves..
Rebuild or build : is to replace damn near everything with the intent do improve either power or longevity or both starting with a core block crank and heads.

There is the basic question, if your 401 is in reasonable shape you could overhaul it "freshen it up a bit and have a nice reliable pretty potent stock engine for bolt on additions later and could be done for 800 to 1200 dollars.

If you are going to "build " it then the price goes up

I just felt the need to type this morning, you guys rerally already answered the question... but hey I am a wordy son of a gun on a good day.! :!:

[CJim7]

I have been reading along and I think there is one small detail that has been overlooked.. the question that needs defining is this: when you say "rebuild" do you mean REBUILD?? or overhaul it seems like those two words get used interchangeably.. heres the definition.. to "overhaul" is to replace wear items.. service parts.. rings, bearings and gaskets cam and lifters if needed.. hone/ deglaze cylinders (they usually arent that badly egged) go through the heads and regrind the valves..
Rebuild or build : is to replace damn near everything with the intent do improve either power or longevity or both starting with a core block crank and heads.

There is the basic question, if your 401 is in reasonable shape you could overhaul it "freshen it up a bit and have a nice reliable pretty potent stock engine for bolt on additions later and could be done for 800 to 1200 dollars.

If you are going to "build " it then the price goes up

I just felt the need to type this morning, you guys rerally already answered the question... but hey I am a wordy son of a gun on a good day.! :!:

ok, and therein is the real question. Im thinking (hopeing) more overhaul then rebuild. I know the cam is trashed, that much is obvious, but with the amount of metal that was floating around in the crankcase because of the wrecked lifter and cam lobe, im not sure if an overhaul is enough. I guess i'll know more when i get the engine dissasembled and see how bad it looks.

I meant Comp cam....(Summit is redflagged in my book). I've dealt with Comp cams before and product and support were awesome.

I need to talk to a few shops....i dont want to get 'herded" into a complete rebuild if i only need an overhaul. at the same time, if a rebuild is neccesary, i dont want to put in $5k to $10K for premium performance parts. I just want a running 401 that wont give me trouble for the next several years. (a stock 401 has more then enough power for my little CJ7)

[Goose]

Well If there was a lot of metal floating around,, the crank will probably need work.. but, and I am about to utter sacrilage, If this isnt a big rpm race motor, and the metal didnt get through the bearing babbit material the rods are probably fine as are the pistons etc.. except for measuring the cylinders for "out of round" but I would absolutely plan on a new timing cover and oil pump
There is a lot of "forgiveness" built into the big American V8's you can get away with things that "aint right" by the book for instance.. the old way to put bearing shells into crank/rods was to clean them with laquer thinner, then times changed and the hot setup was to clean them with Lanolin ??? then we scothcbrited the back and put them in dry (this all refers to the back of the shells not the face).. it all works, no secret recipe..Except CLEAN CLEAN CLEAN.

Me,? I would for sure hot tank it pull the oil galley plugs and spend about a week scrubbing those passages with brushes and a gun cleaning kit, and I would replace the cam bearings with the redrilled variety MC sells here.