Got A 4.0 Head Today

[ThisGuyUKnow]

Well since the Ax15 swap I am still not with an operational CJ7 . For some reason the cj will not stay running at low rpms. I tried taking it to the mechanic to have him tune the carb or see if maybe I just didn't rebuild it correctly and he ended up telling me that basically the intake is sucking air through the space between the head and where the intake ports are. I asked how he knew and he said when the truck was running he sprayed carb cleaner on the area in question and this caused the engine to rev up slightly or whatever.

I got the CJ at the house and tried to do the same experiment and did not yeild the same results;however it is still not driving and he is a proffesional mechanic so I am not going to argue the point.

I already know my Exhaust manifold is warped at the very front and very rear and is leaking real bad(not to mention my rear diff got in a fight with my muffler at some point and the differential won) So I have been putting off replacing the manifold and figured now is the time since it would seem the intake gasket needs to be replaced, and since they both share the gasket everything needs to come off.

Since the Intake and the exhaust are coming off I figured I would go ahead and do an upgrade I have been juicing over for sometime (1991-1995 4.0 head) as at that point all I would have to do is remove that water coolant thing at the front of the head and unbolt it and pull it out.

Went to the pick and pull and got the head off a 1995 XJ (said manufactured oct 1995 in the door so it may be a 96 + head I am not sure, anyone know how to tell?) The cyclinder of the donor were hideous when I pulled the head so I am sure that it will require some valve work at the machine shop.

I also grabbed the header style exhaust from the same Xj but it has a crack on one of the welds and some rust where it would bolt to the head so I am not sure if a exhaust shop will be able to braze the crack and grind that rust down or not. So I may have wasted my money picking it up.

All in all I walked out with a 95 Xj head w/rockers, pushrods, valvecover, etc, 95 XJ header style exhaust, and Two 91-96? style Intake manifold for fuel injection I found for 112 bucks. Not too bad I guess. I figured someone eventually would need a 4.0 intake in one of the many forums I subscribe to so thats why I grabbed those two intakes.

Does anyone know how much I should expect to pay the machine shop to clean up the head, check it for warping, and do the valve work? I don't want to do anything to crazy, I thought at most have the do a three angle valve top if I really felt I needed anything that performed better than stock.... I really don't even know what that it other than it sounds cool and everywhere I have read on this swap recomends getting it done.
Depending on whether or not the price tag for this gets unreasonable I may have the machinist weld the water jackets but currently I plan on following the "poor man's" method of shoving disolvable packing peanuts into the jacket and then using a high heat epoxy.

I wanted to go ahead and start the thread on this although once I drop everything off at the shop I am heading back to Illinois again for some college graduations. I may go ahead and pull the old intake and exhaust manifold tomorrow but then it will be a few before I can put the new head in.
Pic of the Goodies

 

[ThisGuyUKnow]

Thought I would add that I plan on running the stock AMC 258 i6 / 4.2l intake and carb once I get the head and exhaust header on. I will eventually go 4.0 injection as well but my pocket book is getting mad at me.

 

[IOPort51]

I offer one bit of advice. When you re assemble put the head and manifolds together before you put the head on the engine, go ahead and do the first torque on everything, It is a whole lot easier than putting the manifold on with the head bolted down. You will need help or a hoist to set the head .

Well since the Ax15 swap I am still not with an operational CJ7 . For some reason the cj will not stay running at low rpms. I tried taking it to the mechanic to have him tune the carb or see if maybe I just didn't rebuild it correctly and he ended up telling me that basically the intake is sucking air through the space between the head and where the intake ports are. I asked how he knew and he said when the truck was running he sprayed carb cleaner on the area in question and this caused the engine to rev up slightly or whatever.

I got the CJ at the house and tried to do the same experiment and did not yeild the same results;however it is still not driving and he is a proffesional mechanic so I am not going to argue the point.

I already know my Exhaust manifold is warped at the very front and very rear and is leaking real bad(not to mention my rear diff got in a fight with my muffler at some point and the differential won) So I have been putting off replacing the manifold and figured now is the time since it would seem the intake gasket needs to be replaced, and since they both share the gasket everything needs to come off.

Since the Intake and the exhaust are coming off I figured I would go ahead and do an upgrade I have been juicing over for sometime (1991-1995 4.0 head) as at that point all I would have to do is remove that water coolant thing at the front of the head and unbolt it and pull it out.

Went to the pick and pull and got the head off a 1995 XJ (said manufactured oct 1995 in the door so it may be a 96 + head I am not sure, anyone know how to tell?) The cyclinder of the donor were hideous when I pulled the head so I am sure that it will require some valve work at the machine shop.

I also grabbed the header style exhaust from the same Xj but it has a crack on one of the welds and some rust where it would bolt to the head so I am not sure if a exhaust shop will be able to braze the crack and grind that rust down or not. So I may have wasted my money picking it up.

All in all I walked out with a 95 Xj head w/rockers, pushrods, valvecover, etc, 95 XJ header style exhaust, and Two 91-96? style Intake manifold for fuel injection I found for 112 bucks. Not too bad I guess. I figured someone eventually would need a 4.0 intake in one of the many forums I subscribe to so thats why I grabbed those two intakes.

Does anyone know how much I should expect to pay the machine shop to clean up the head, check it for warping, and do the valve work? I don't want to do anything to crazy, I thought at most have the do a three angle valve top if I really felt I needed anything that performed better than stock.... I really don't even know what that it other than it sounds cool and everywhere I have read on this swap recomends getting it done.
Depending on whether or not the price tag for this gets unreasonable I may have the machinist weld the water jackets but currently I plan on following the "poor man's" method of shoving disolvable packing peanuts into the jacket and then using a high heat epoxy.

I wanted to go ahead and start the thread on this although once I drop everything off at the shop I am heading back to Illinois again for some college graduations. I may go ahead and pull the old intake and exhaust manifold tomorrow but then it will be a few before I can put the new head in.
Pic of the Goodies

 

[ThisGuyUKnow]

I offer one bit of advice. When you re assemble put the head and manifolds together before you put the head on the engine, go ahead and do the first torque on everything, It is a whole lot easier than putting the manifold on with the head bolted down. You will need help or a hoist to set the head .

So you are saying while i have the head off I should torque the exhaust and intake onto it? Won't that make it a PITA trying to drop it onto the block? I am curious if i will have anyissues getting the old intake and the new exhaust to play nice?

 

[IOPort51]

not nearly as big a PITA as getting the manifolds lined up and reaching the bolts to get proper torque on all the bolts. And you will get the chance to put the wrench on after 500 miles to re torque the bolts.

So you are saying while i have the head off I should torque the exhaust and intake onto it? Won't that make it a PITA trying to drop it onto the block? I am curious if i will have anyissues getting the old intake and the new exhaust to play nice?

 

[ThisGuyUKnow]

not nearly as big a PITA as getting the manifolds lined up and reaching the bolts to get proper torque on all the bolts. And you will get the chance to put the wrench on after 500 miles to re torque the bolts.

Is the 3 angle valve job worth the extra $$$$? I see u did it on your head. I was just goig to have it refit to stock to save money but if it is worth it.....

Are u running the carbed intake? What exhaust did u use? Which head gasket did you use? Also which intake gasket did u use? The ones for a AMC 258 i6 / 4.2l ? Or for the 4.0? Do you have to grind away any metal to get the intake and exhaust to fit.

 

[IOPort51]

I don't think the 3 angle will cost much more than a stock grind but check with your machine shop It has been SOP for me for quite a few years.
I use a carter 2 bbl carb. the head is 4.0 the intake is AMC 258 i6 / 4.2l the exhaust is a cheap stainless steel header that fits the 4.0 that I found on E-Bay. I preferred the header to the stock 4.0 exhaust as I hope it will not be as inclined to crack. SS has a very high rate of expansion and even with the expansion joints the stock don't have enough flex.
use the AMC 258 i6 / 4.2l manifold gasket and the 4.0 head gasket.
There is a small bit of grinding that is needed on the intake manifold to mate with the exhaust, another good reason to assemble this before you set the head.
I think you have 1/2 inch head bolts but if you have 7/16 head bolts you will need some shims from Clifford to keep the head centered.

 

[ThisGuyUKnow]

Local exhaust shops wont touch the header I picked up =(. Barry's upull says they take returns but I can't find the receipt so its doubtfull I will get my $$ back. How about this?
91 92 93 94 95 Jeep Grand Cherokee Exhaust Manifold 4.0 : eBay Motors (item 110530888485 end time May-12-10 15:56:02 PDT)

 

[ThisGuyUKnow]

The machinist said I was looking at 210 worst case scenario to magnaflux the head remove the broken stud and cut the valves at three angles. I guess hats not bad but he saidthere was about a 50/50 chance a junkyard head will be any good. Seems pessimistic to me but I hope it will work out.

 

[IOPort51]

He is telling you true, they like to crack between the valves. AMC 258 i6 / 4.2l 's are worse.
Gibson Stainless Headers 1995/1996 Jeep Grand/Cherokee : eBay Motors (item 400103912180 end time May-17-10 12:55:36 PDT)
these are pretty close to what I used on my truck but I don't see any reason not to use the stock header. I would find a welding shop to do the crack rather than a muffler shop. some one who can run a stainless steel rod should not be too big a problem.

The machinist said I was looking at 210 worst case scenario to magnaflux the head remove the broken stud and cut the valves at three angles. I guess hats not bad but he saidthere was about a 50/50 chance a junkyard head will be any good. Seems pessimistic to me but I hope it will work out.

 

[ThisGuyUKnow]

He is telling you true, they like to crack between the valves. AMC 258 i6 / 4.2l 's are worse.
Gibson Stainless Headers 1995/1996 Jeep Grand/Cherokee : eBay Motors (item 400103912180 end time May-17-10 12:55:36 PDT)
these are pretty close to what I used on my truck but I don't see any reason not to use the stock header. I would find a welding shop to do the crack rather than a muffler shop. some one who can run a stainless steel rod should not be too big a problem.

ok IO not to be rude but if those are the headers you used then you and I have a different definition of cheap. 400 bucks? What abot he ones I linked for 85? Maybe I should just weld it and if it cracks again just reweld It over and over? Will the cheap ones I found not perform well?

 

[IOPort51]

We pretty well agree on what cheap is, and these are not They are a lot less than a good header . If I were in your shoes I would weld the ones you have. Before you send the head to the machine shop I suggest you bolt the manifolds to the head, pre heat a bit with a torch and weld the crack. If it is going to crack it may do it right after it is welded. I would have a talk with someone at your local welding supply for rod recommendation. the ones I have seen in the junk yards that were re welded were welded in place while still on the car. They were pretty sloppy and it is no wonder they cracked again.

 

[ThisGuyUKnow]

We pretty well agree on what cheap is, and these are not They are a lot less than a good header . If I were in your shoes I would weld the ones you have. Before you send the head to the machine shop I suggest you bolt the manifolds to the head, pre heat a bit with a torch and weld the crack. If it is going to crack it may do it right after it is welded. I would have a talk with someone at your local welding supply for rod recommendation. the ones I have seen in the junk yards that were re welded were welded in place while still on the car. They were pretty sloppy and it is no wonder they cracked again.

what about that ss headers I linked In an earlier post? They are only 85 bucks and may be less hassle than me trying to learn to weld

 

[ThisGuyUKnow]

Machinist called today, the head is magnufluxed and is free of cracks. Now he is just going to cut the valves at three angles and put it back together.

 

[ThisGuyUKnow]

Hey admins, delete this thread or merge it with

Installing a 4.0 Head and MPFI on My 82 258 please. I kinda started two diff threads on the same subject.

Tim