4AGE BT: To Keep or Not to Keep

4AGNoob
Posts: 4
Joined: Fri May 03, 2024 7:38 am

4AGE BT: To Keep or Not to Keep

Postby 4AGNoob » Fri Jun 07, 2024 9:19 am

I have an opportunity to buy a 4AGE blacktop for $1300 or return it. The engine is in my garage and I have a few days to make a decision. The guy I bought it from checked the compression, and it measured between 230 and 250. My hesitation on keeping it is the amount of carbon build up in the head. See the attached picture. What do you guys think?

Image

davew7
Club4AG Expert
Posts: 239
Joined: Fri Jun 06, 2014 4:34 am
Location: Michigan

Re: 4AGE BT: To Keep or Not to Keep

Postby davew7 » Sat Jun 08, 2024 4:17 am

If the engine is really reading that high in compression, then it is probably in very good shape. I would just make sure to use a good oil and filter and change it several times after installation.

4AGNoob
Posts: 4
Joined: Fri May 03, 2024 7:38 am

Re: 4AGE BT: To Keep or Not to Keep

Postby 4AGNoob » Sat Jun 08, 2024 12:58 pm

Gotcha. I guess there could still be bearing issues in my future, but the compression would suggest the piston rings and valves are ok?

What would you recommend for cleaning the head?

davew7
Club4AG Expert
Posts: 239
Joined: Fri Jun 06, 2014 4:34 am
Location: Michigan

Re: 4AGE BT: To Keep or Not to Keep

Postby davew7 » Sun Jun 09, 2024 3:42 am

There is really know way to tell about the bearings. You could send the oil out for analyst. You have to be careful cleaning. You do not want large pieces falling into the sump that could block the screen on the oil pump pickup tube. I would add one qt of diesel oil to the next couple of oil changes, which has a higher level of detergent.

totta crolla
Club4AG Pro
Posts: 656
Joined: Tue Mar 26, 2013 5:21 am
Location: Oxford U.K

Re: 4AGE BT: To Keep or Not to Keep

Postby totta crolla » Sun Jun 09, 2024 12:16 pm

If you want a blacktop that is pretty much what you expect to see.
If it came as a complete unit $1300 is cheap so would be worth rebuilding should you need to.

4AGNoob
Posts: 4
Joined: Fri May 03, 2024 7:38 am

Re: 4AGE BT: To Keep or Not to Keep

Postby 4AGNoob » Mon Jun 10, 2024 4:13 am

Good thought on cleaning and not wanting bits falling into the sump. I was thinking of cleaning with engine on a stand, sump up.

Mixing a quart of diesel oil in is ok? I've never mixed oils before.

allencr
Club4AG Expert
Posts: 398
Joined: Thu Jan 10, 2013 9:59 pm

Re: 4AGE BT: To Keep or Not to Keep

Postby allencr » Mon Jun 10, 2024 11:06 am

Wet or dry? The compression test? That is REALLY high, a happy gauge or a LOTTA buildup in there. Can you see anything in there?

Do nothing or do it completely or just the pan & the pickup ONLY to make sure it'll have no pickup problem no matter what else is wrong.
The cleanliness/flush/douche stuff for engines does no good for an engine, just makes you feel good & like you're doing something not futile, that old 'cleanliness is next to godliness' BS. The built up **** ain't pretty but what harm does it do except the potential pickup clog when YOU start doing stuff, and insulate heat dissipation, and clog rings that nothing but disassembly will cure. It's baked on pretty tight & requires some push to dislodge doesn't it? Either leave it or clean it completely, not bright & shiny, but nothing that will come off without a wire brush, and the results would be the same to the engine's moving parts that are in contact with each other, nothing.
We know you wanna do something, first rule, don't **** it up. Then, are the crank seals weeping a bit or have a noticeable washed out trail leading from them? Cam & distrib. seals? Water pump weep hole corroded & have a trail?
Most regrets are from starting off doing a little that just snowballs into more then you've got time & $$ & ability/knowledge to do, then the regrets are from not doing more to start with right off the bat, no piecemeal ****. Toss a coin?
Good luck.

4AGNoob
Posts: 4
Joined: Fri May 03, 2024 7:38 am

Re: 4AGE BT: To Keep or Not to Keep

Postby 4AGNoob » Tue Jun 11, 2024 8:28 am

I believe the compression test was dry. The supplier sent me a video of the test with the engine uninstalled. What would I be looking for to see buildup that would cause high compression?

allencr
Club4AG Expert
Posts: 398
Joined: Thu Jan 10, 2013 9:59 pm

Re: 4AGE BT: To Keep or Not to Keep

Postby allencr » Thu Jun 13, 2024 9:57 am

A THICK coating of carbon, like 2-3mm 1/8in over everything in the chamber & piston top. I think/guess it won't be pretty hard carbon like a high mileage carburetor engine, but a lotta light soft play-doh like stuff built up from burning lots of oil.
Then again, those numbers are from someone selling, trying to impress you, their spread isn't too bad and there are no dead holes, so I'd say it's a keeper cause there's no telling what you'll get next.
The poor maintenance is off putting, crank & bore & valve wear should be expected in any engine but a wrecked late model. If you wanted plug&play, try it, you can't make it any worse then it is unless it was ready to throw a rod, loose a valve or have a piston come apart already.