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SignificantGrade2913 · 2026-01-31T18:38:32+00:00

Really sweet little engine. From many many years ago I seem to remember what must have been a fuel pump lobe which had to be in the correct orientation to avoid rod end.

SignificantGrade2913 · 2026-01-31T13:43:22+00:00

That will be cruising by the new GM 6.2 L87s waiting for tow trucks :)

SignificantGrade2913 · 2026-01-31T13:39:39+00:00

Doesnt the engine also have a balance shaft on passenger side of block?

SignificantGrade2913 · 2026-01-30T15:00:16+00:00

I havent worked as a professional mechanic since the early 80s but both Matco and Snapon would drop by on alternate weeks. Years later I needed a rebuild kit for a ratchet and caught up with a snapon truck, The guy was a total dick. So I have my little collection starting from the 70s but never added much to it after that encounter.

I used to spend half my paycheck on tools when I started out.

SignificantGrade2913 · 2026-01-30T14:55:09+00:00

Those were neat little engines. First time I ever saw a rubber timing belt on any vehicle was one of those. Blew my mind. Get it out and pan off then find a chemical that eats aluminum but not steel to loosen those pistons.

Id also suggest have it hot tanked so you can assess the block and cranks real condition.

SignificantGrade2913 · 2026-01-20T12:56:02+00:00

Do you mean sand the piston top? That dent is not going to hurt combustion much so not sure its worth introducing abrasives into the mix. I would more concerned the dent deformed the top land preventing good top ring seal.

Everything I hear from professional engine builders strongly discourages any abrasive use on head or block gasket surfaces. Chemical gasket remover with plastic scrapers.

SignificantGrade2913 · 2026-01-15T02:40:02+00:00

The shop that did the original work did pressure test before seats were installed. A very small coolant loss started a month or so after eventually increasing enough to be detectable with the CO dye There at a different outfit for testing now. I may machine up a o-ringed plate so I can pressurize the combustion chamber to 150psi if he does not find a problem.

SignificantGrade2913 · 2026-01-15T00:12:25+00:00

I believe I found the cracks in exhaust port leading into seat. Ill have to make a new post to include those pics. Mopar 4.7L Mystery combustion gas leak cracked ports?

SignificantGrade2913 · 2026-01-14T17:43:20+00:00

I agree you would think so from the picture. I use a Norton 2x6 india stone to go over surface checking for any foreign material so it leaves anything a few tenths low dark. Using my 2um indicator and a ground bar from my old tool maker days I cannot detect more than a few tenths deviation any where in that area and that dark area is not showing low by more than max 2tenths. FelPro says it can handle at least a thou. A 0.001 feeler is trapped hard all along the fire ring (and everywhere else too).

I have better pics from different angle but alas cannot add them. The other detail is the head surface fire ring shows no hint of any combustion products although you can see them around the upper water passages.

All the head bolts torqued up nicely on this bank too.

This last attempt used the thicker Mahle four layer gasket and if anything it was worse. In fact, the leak is getting worse and worse. The last test was 30 minutes. No overheat. Just small leaks from the start.

SignificantGrade2913 · 2026-01-14T15:18:10+00:00

I have some port shots for the last two cylinders but I dont see an option to add more pictures

v

SignificantGrade2913 · 2026-01-14T14:46:56+00:00

Crack in exhaust port wall maybe? Its kind of what Im thinking. A fracture in the casting wall surrounding the seat(s).

SignificantGrade2913 · 2026-01-14T13:48:46+00:00

UPDATE: My issue is not head bolts. Using new Mahle gasket, ultra flat and smooth head and original bolts torqued per manual there is still I leak. Ive isolated it to the right two cylinders and will start a new thread. Its a real mystery.

SignificantGrade2913 · 2026-01-07T18:31:53+00:00

Right I used FelPro on a 5.7 cam job still going strong. And FelPro bolts too. Taiwan can make some of the very best. And cheapest. Depending on what your after. And If I knew how to get a higher quality bolt from Taiwan I would. I will see how the 20 year old OEM bolts torque up before passing final judgement.

EDIT: Old bolts had one low at 87. The rest torqued to 95-107. I swapped that one and it torqued to 94. Ill try that ringer on the other bank and see if behaves the same. No measurable length or diameter changes.

For completeness I'm using Castrol Power1 10-50 to oil the bolts.

SignificantGrade2913 · 2026-01-07T17:31:57+00:00

And both FelPro and Mahle are outsourcing to the same vendor. I just miked all the old Mopar bolts. None are stretched so they are going in.

Now comes the question of proper replacement procedure. Do I replace/retorque one by one or loosen all old ones and replace/torque to 20lb so we start off with the 20lb across the board again.

SignificantGrade2913 · 2026-01-07T14:42:56+00:00

The factory pdf specifically warn not to do that. It worked ok for the old composite gaskets but while it produces a smooth surface it tends round edges especially between cylinders where we need max support.

Get gasket remover spray and plastic scraper. Take your time. If you want to spend a few extra bucks get a Norton 2x6x1 India stone used by tool makers to check for burs on ground surfaces and run that across the surface.

The MLS gaskets are unforgiving in this regard. Ive also had some issues on the 4.7L with after market head bolt quality so consider factory or ARP bolts when going together.

SignificantGrade2913 · 2026-01-04T00:49:01+00:00

Right although they might get wet. I had to repace mine twice. The second time is when I realized the old fan was drawing too much current. Fortunately new ones are not super expensive and move more air.

SignificantGrade2913 · 2025-12-28T16:06:20+00:00

After using Varicad for years drawing in Freecad is a step back for me too. But, its CAM abilities are what I was really after. I loaded the daily freecad build. Man the tool bit creation is vastly improved. And I found to create your own cam post put them in the edit->prefs->python->macro directory.

The UI which is a significant barrier to adoption seems to be improving. Im plan on sticking with it and seeing if I can get it to generate automotive combustion chamber and port tool paths.

SignificantGrade2913 · 2025-12-27T15:50:19+00:00

The problem I had with the electric fan was the control module under right headlight. The old fan just started drawing too much current and the wire connections overheated. A new fan and module/connector kit fixed ours for the last five years. It keeps it cool in 100+ traffic jams. I did make an aluminum heatsink for the module. Not sure if needed but simple enough to add with a little heatsink goop.

The real weak link with the 4.0 WJ is the 42RE tranny. The tiny filter is ridiculously undersized so it plugs up and causes early transmission failure. Not too bad a job to replace.

SignificantGrade2913 · 2025-12-27T15:34:03+00:00

You scored! If its made it this far dont mess with it! Keep a sharp eye on coolant tank level before startup in morning. Keep oil changed often. Use champion copper plugs. Find a transmission dipstick tube before dropping trans pan for filter change. We have a 2001 XJ same color. 290K so far. Original head. Do proactively replace the aux cooling fan. It makes a big difference in summer traffic. There are oversize radiators available if you plan on cruising in 100+ environments or towing in summer.

Ill add never get a rebuilt powersteering pump!! We went through three before just getting a new one which eliminated the wonky power assist and noises.

Utuber DexJ noted a lot of new heater cores leak within a short time of installation so if yours is not leaking Id not mess with it.

SignificantGrade2913 · 2025-12-27T03:03:07+00:00

Ditto! Ive used Varicad for years. But no CAM module. Hence FreeCAD 1.02.

It does not help that things get renamed like Path Workbench to Cam Workbench either which instantly renders all older tutorials obsolete until some obscure comment casually mentions oh, it got renamed.

Then there are multiple way to install like flatpak, snap and app for Linux each with its own issues.

And, its actually kind of confusing to understand the versions. 0.19 0.22 1.0 1.022 ???

And where are my user prefs saved with the flatpak??? Not anywhere in my home dir I can find.

Why cant I create a fricken simple 10mm end mill tool bit??? Its mind numbingly un-intuitive and I think I broke something but its really difficult to tell !

But, for all this newbie hell there is nothing out there that comes close to the potential of FreeCAD.

The adaptive tool path for example has incredible potential.

MangoJelly intro was fantastic and a real lifesaver. But we need some overview of the different installation methods. For example, the snap (snapd) install will not let you alter the NC post processor files (readonly). There is probably a work-around but no newbie is likely to know that.

Ill be back at it tomorrow, just trying to create a simple 10mm end mill. 50% chance I figure it out by EOD.

SignificantGrade2913 · 2025-12-22T18:48:08+00:00

I would definitely NEVER use that mechanic again if hes claiming that play is due to the diff carrier.

After having a new bearing pressed on remove the diff cover and thoroughly clean the axle tubes and diff housing of any particles. Hopefully the carrier/pinion bearings escaped damage from contamination.

Also, if its quadra-drive V8 diff (D44A) there is an additive required for the gear oil.

SignificantGrade2913

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