So I have been avoiding checking the things you can check to maybe get a handle on the condition of your engine. '00 XJ 4.0. Ignorance is bliss and all that.

Compression test, hooking up a mechanical gauge to check oil pressure, etc.

Thinking I am going to do every test under the sun. While I can probably borrow or rent most if not all these tools I am justifying purchasing them as a birthday present to myself. Big 60 in less then 2 weeks.

Leaning towards OTC and Stant. So figure I would ask people much smarter then me about tool choices and any tips using them.

First thing is one of those block testing kits.

https://www.napaonline.com/en/p/BK_7001006

Now I do have a question about using this. You put it in the radiator but make sure that you take out enough anti-freeze so you don't suck any up to screw up the test. Also checking hotter appears to be better. So you can't remove the radiator cap when hot and letting it run while open to get hot will just result in anti-freeze coming out. So can this test be done from the overflow tank? Will you get a valid result?

Other tools I am considering:









Now I can get these much cheaper. The links are just to show you what I am considering. And yes I realize this is overkill and I can find better things to spend money on. But........

Any and all tips or suggestions will be appreciated.

 

I have done a lot of diagnostics on 2 XJs (98 and 99) and a 95 YJ. I wouldn't invest in buying any of the tools until you need them. If you want to get a general condition check, I would go this route:

1. Compression test, dry and then wet (cylinders should be within 15% for highest and lowest)
2. Fuel pressure test. Should by ~50 psi at the fuel rail running
3. Leak down tester - this will check top and bottom end (may not be able to rent this one, but can get a decent one for $50)

You do have a '00 which can be prone to the head crack. I don't have experience troubleshooting that problem.

If it were me, I'd find some other places to spend that money on your XJ instead of the tools that you will most likely use one time.

 

Ralph, do you ever have oil analysis done? It's something to consider for '00 and '01 owners, as it would reveal any issues with coolant mixing in the oil even in minute amounts.

 

One thing I forgot to mention that I am doing. Most likely in a couple weeks.

 

The cylinder head on 2000 and 2001 can crack just under the oil cap and it doesn't usually blow and put exhaust in the cooling system . If they crack it will put coolant in the oil .

 

So you are saying using the block tester is probably a waste of time?

 

I think almost all of it is a waste of time other than the oil analysis.

 

This is just my personal opinion, Ralph, so take it for what it's worth...I would have the oil analysis done by Blackstone Labs since, as has been pointed out, it will reveal a significant amount of usable info. Pending those results, I would save my money on tools/equip unless I used them frequently.

I would also perform a compression and a leak down test just to satisfy my curiosity on the general condition of certain components, but, again, I wouldn't buy the tools if I didn't plan on using them frequently.

Edit: In case you're wondering why the redundancy of a compression test and leak down test even with oil results? It's just my ****-retentive nature; nothing more. Otherwise, I agree with cruiser.

 

I am kinda thinking of not doing some of this stuff now. Been picking the brains of a few mechanics at the places I deliver too. Plus what you guys have been advising.

The oil analysis is going to happen. Been holding on to the Blackstone mailing kit to use it. I picked up a Gearwrench compression tester for $5. Sears Shopyourway points strike again. I can borrow my buddies leak down tester but I really hate borrowing tools even though he won't even think twice about lending it to me. Plus he was asking me about the OTC oil pressure kit. Thinking he is going to buy one of those which means I can borrow that too. So I haven't ruled out buying the leak down tester or the mechanical oil pressure kit. Despite the fact that as 4WD4EVER said for the amount I would actually use it not worth the expense.

 

In my case, I did the compression test just because I was replacing the spark plugs anyway, and it seemed worth the slight extra effort to have that data.

I'm awaiting my Blackstone analysis at the moment before pulling the trigger on some of the bigger fixes on my 95. This is the first time I've done oil analysis, but the price was very reasonable and from the example reports it looks like a lot of valuable, yet easy to understand data.

 

I had to buy an oil pressure test gauge as none of my local parts retailers had them as loaner tools.

I paid like $18 at Harbor Freight. If I would get more than a couple uses out of it, I'd have sprung for a more quality tool, but since it was something I knew I'd probably use once or twice I went with the cheapo. It worked perfectly for me - confirming that the pressure from my gauge was accurate.

 

I was looking at the HF oil pressure kit. People seemed to like that one. Was considering that too. People did not really seem to like their compression and leak down testers though.

 

AutoZone (or other parts retailers) have Compression test gauges and leak-down testers available as loaner tools. The Autozone compression gauge worked fine for me and the price was right!

 

I agree 100%.

Borrow what you need for a compression test.

Check your oil pressure with a mechanical gauge. I picked up a Bosch for under $20 (I think it was $16.99 on sale) just for that. Sure it doesn't have a fancy blow-molded case, but it reliably measures oil pressure, and it takes less than 10 minutes to remove the existing sender, connect the Bosch, set it on the cowling where I can watch it, fire it up and read the pressure, then put it all back to stock.

 

i agree with this. something to add - i’ve dealt with engines for a long time and i’ve never went looking for a problem. also never had an issue that could not be resolved...everything can be repaired one way or another.

much like anything else in life - go digging for trouble and you will find it, whether it’s really there or not.