Tired Motor (time for a rebuild)

[ROLNBLOK]

My motor is starting to show signs of wear. Mainly very little oil pressure when ideling in 4lo for extened periods (1-3 lbs on my guage). I replaced the sending unit and the reading is still the same. However, at highway speeds and around town my pressure is up around 26+ pounds.

So I was thinking I might rebuild it this winter/early spring. However, I was wondering if anyone has suggestions on a good book that walks one through a rebuild. The last motor I built was a 327 sbc and I had a great reference for that project (How to rebuild small block Chevy book). Is there anything like that for the 4.0l Jeep motor? Also, I read that the newer 4.0s have different pistons to help reduce the piston slap noise that plagued earlier 4.0s. Are there good aftermarket cams that still work with the computer to help low end torque? I am in the early phases of research for this project and any help/references will be greatly appreciated.

Thanks.

PS, I do not want to hassle with an engine swap/stroker as I am mostly happy with the 4.0 and do not have the time/resources to fool with something like that.

[NJJeepYJ]

There is a book "JEEP ENGINES" I believe quadratec sells it.

http://www.quadratec.com/cgi-bin/sgin0101.exe?T1=19005+00&UREQA=1&UREQB=2&UREQC=3&UREQD=4&FNM=00&UID=2003081310515240

[Jimbob]

Ouch that is lousy oil pressure

I get about 45 psi at over 35 mph, with a drop to no less than 30 or so at idle.

[ROLNBLOK]

Thanks for the reply,

I saw that book in qadratech. However, I guess I am looking for recommendations. Is it a good book or not? I hate to buy a book (or anything for that matter) from a catalog or online with out having some idea of what I am getting.

The description is a little vague to me:


The updated official Mopar Performance Parts guide to Jeep Engines will show you the way to high performance engine modifications for a variety of applications. Authors Larry S. Shepard and Michael Gingerella examine race engine setups, engine blueprinting and many mechanical details of the powertrain for a wide range of Jeep vehicles. Includes coverage of 4,6 and 9 Cylinder engines back to the AMC days. 498 fact filled black & white pages. Highly technical.

I am sure that it discusses ways to tweak power out of the engines and mechanical theory as well as blueprinitng specs that would be useful for the machine shop to have. But does it provide the torque sequence for the cylinder heads, main bearing clearances, ets., or is it a book dedicated on how to turn a 4.0 into some sort of race engine?

I am not opposed to buying the book and I guess it is as good a place to start as any. I would just like to know if anyone has it and if ( in their opinion) it was a worthwile reference while rebuilding an engine or is there a better book outhere?

[Ron90YJ]

if you want the torque specs any chiltons/haynes/FSM will have that information. I used to have a book "Basic Engine Rebuilding" that was a wealth of knowlege useful to any engine rebuild. Since you are not interested in making a real performance motor just some internal upgrades look at comp cams profiles and the operating range, or call them and let them know what you are wanting, you will probally get an RV grind cam good low end TQ. Sealed Power makes pistons with coated skirts which are an excellent replacement for a stock piston. Since you are doing a rebuild and want a bit more power I would recommend having a machine shop bore the cylinders .030 over since you will be replacing the pistons anyway. That will also take care of any taper or out of round on the cylinders. Oh and the only difference between a standard rebuild and a stroker is putting a 258 Crank/Rods in and going to 24# injectors.

[DPTDAWG]

I too had to do some engine work. The option I chose using time available, performance, and cost as my deciding factors, was to replace my old 4.0 with a reman from a parts store. The cost was about the same as rebuilding my old one, but the time was much shorter. I too was happy with the performance I had, and did not want to take the additional time and $$ for building a stroker or putting in a V8 etc.

Just a thought

CJ

[ROLNBLOK]

I have considered a reman motor as well as a used one from a junk yard. It would save substantially on the down time. However, I havent had an engine apart in about 10 years and I quess I sort of have a hunkerin try it.

The one positive about the remanufactured one from a parts store is the warranty. I guess I will start with a few books and go from there.

Thanks for the suggestions and information.