Rebuild vs. Re-ring vs. Replace with used engine?

[waterdog]

1990 with ~210k miles, compression not much over 100 (~150 wet), so I'm looking at either rebuilding, re-ringing or replacing with a used JAP engine (which I can get for ~$600). The used engines from Japan supposedly with ~30-50k miles and checked for compression.
My engine seems good except for the compression. Has anyone done just a ring and hone job, (and maybe a valve job)?
I think the cost of rebuilding this engine would be pretty expensive, anyone have some cost figures to compare?

 

[Doward]

Depends on how you rebuild. A stock styled rebuild with MHG + ARPs = $2k-$3k. Forged bottom end = $4k-$5k. I'm currently at ~$6500 in my engine.

 

[KongGMC]

Not familiar with the cost of redoing the bottem end but I know I've pretty well tallied up a very simple rebuild on the top end of my engine at around $850ish. That's without the fancy head gasket and ARP head bolts. The machine work for the head alone is gonna run me $450. I figure the bottom end would probably cost twice this unless your just talking about honing it yourself and replacing the rings and bearings all yourself.

 

[AJ'S 88NA]

I'd rebuild the original. You should at least tear down a JDM, check everything out, new oil pump. I've went the JDM route and was sorry I did, ended up rebuilding my original.

 

[cuel]

Used motors are not a good way to go. You don't know how it was maintained, how badly it was beat on, or anything else. Rebuild will cost a bit more, but be well worth it in the long run.

Check everything. All the bearing tolerances, bore size, etc. If its all within spec., you could get away with just freshening the bottom end(new rings and bearings). I'd get a new oil pump, water pump, timing belt, all new seals and gaskets, at a minimum. If the tolerances are at the upper limits of the specs in the tsrm, I'd get everything into the machine shop, and have it fixed. You can get .020" over cast pistons from BAP Geon for around $250 to $300 a set, including rings. They also carry pretty much everything you could possibly want for an import, at reasonable prices.

 

[Kckazdude]

I have done re-rings on the cheap for other people and on my throw-away motors (engines in my 4x4 that I would be taking to water runs). As long as you dont expect them to last long or over perform they are an inexpensive alternative.

However, if you want your engine to last a while and perform properly, follow cuels advice above.

 

[afofsupra]

What he said ^^^
I'm with AJ, the JDM is gonna need a few hundred minimum. Mine had spun bearings so it was exactly like the one I was planning on replacing.
I don't see why a motor that is in spec would need anything more than polishing and new bearings/rings. If it is destined to be a normal commuter. Is it turbo? I'd do more on a turbo motor due to the added stress.

For a shop to spec, clean & polish bare block, crank, rods & head, should be $500 or less. The more work they do (disassembly, grinding, boring...) the more it costs.

What are your plans for this motor & car? Expecting to change in 5yrs or so? Alot of factors go into the decision on how much to spend.
For my money, there aren't any new cars in this price range that are comparable.
You could through $10,000 into a MKIII with good body & interior and know you are good for another 200,000 miles with a quality car. You'll never recover that money in resale.

I have 2 that I'm doing, both NA, both 87. I plan on rebuilding both motors. Nice daily drivers for the money.

 

[waterdog]

Sounds like a lot of bad experiences with used JDM engines; anyone have any good experiences?
7M-GE, looking at something relatively inexpensive, easy and works, have no plans of selling it at this time, used as a basic 20 year old driver. So if I can get a set of pistons for a few hundred and the other major parts are in spec then a rebuild may be in my range. I can do a lot of the work myself (just need to make time and space) and have friends that can help with machine work and such.
What internet sites have good deals on Supra parts? I've used RockAuto but some parts could not find there, such as the breather hose on the left side just below the oil filler cap that snakes down behind the alternator down to the block. Mine is old, hardened and making a mess leaking oil. Has anyone replaced this hose? Do I have to use an original preformed hose or can I just use a plain piece of proper size rubber tubing?

 

[p5150]

That hose is a dealer part that costs about 20 bucks.

the tsrm website has an Electronic parts catalog that you can get part numbers from. Once you have a number run it through www.toyotapartscheap.com to see the price.

 

[afofsupra]

I don't see why you couldn't use a hose of the correct size, provided it doesn't kink.
Before you do anything else, either pull the motor, or drop the oil pan (i'd pull the motor).
Pull the the rod caps to see what's bad & how bad. Find a machine shop. It's unlikely that the piston bores are in need of anything more than honing, but you won't know until you pull it. Provided you only need cleaning, polishing, surfacing (of head & block deck) and the crank doesn't need to be turned (or block line honed) I'd expect under $500 for machine work, figure another 200 for turning crank, $150 to turn all 6 rods and another $200-300 to line hone block.
Bearings, rings & gasket kit ~$300. So expect the neighborhood of $800 - $1500 to rebuild w/ new headgasket, rings, bearings & all gaskets.
$650 for JDM / Used $150 for gasket kit, best luck puts you at ~$800 JDM w/ new headgasket...worst luck puts you rebuild as above + $650 for the JDM core.
Any JDM or Junkyard motor should be torn down unless you can hear it run in the car. Rod knock & bhg are too common to not expect.

ps- you really need new head bolts too....

Also, Champion (formally Jaymarks toyota) is online.

 

[Kckazdude]

I don't see why you couldn't use a hose of the correct size, provided it doesn't kink.

As long as you use the properly rated hose for oil. This isnt readily available at your local AutoZone or competitive parts store. If you were to use heater hose for example, within a month it would be all soft and oil impregnated. Basically a waste of money.

 

[Fuzz420]

My vote is for rebuild

Went with the JDM route a few years back, and when it was ok and worked fine up until recently(BHG). When it was all said and done it cost me roughly $1500-1600, to have the motor "ready" to go in. In perspective now, im rebuilding a GTE, and it cost $1600 for complete rebuild+ forged pistons+mhg+prepped rods+arp's for the head and rods, and machine work. Forge pistons, mhg, and head studs are not included in the over all price, and only adds $600 in parts for the total. For a minute money difference i have far superior setup. Goodluck in which ever route u decide to take

 

[afofsupra]

As long as you use the properly rated hose for oil. This isnt readily available at your local AutoZone or competitive parts store. If you were to use heater hose for example, within a month it would be all soft and oil impregnated. Basically a waste of money.

truth!! I get large fuel & oil lines at a industrial hose supplier, they have any and all hoses for industrial use and often the hose size you need they may only have in stock in a rating that cost more than the dealer hose. Mainly good for older cars where there exists no dealer option.

 

[p5150]

In this instance I think you should purchase a dealer part. The bend right out of the top of the valve cover will be tough to replicate. A straight hose will kink. Plus the stock hose is a metric size so you will probably have to use a hose clamp or force a smaller hose onto the valve cover nipple. Its really not a very expensive part.

 

[labrat469]

Go for the rebuild. With any used motor you are just going to end up rebuilding it. The course I went was to rebuild the original for a daily driver then got another used motor to build up later on money permitted.
After the rebuild you need to baby the motor until it breaks in. I set my break in period at 500 miles. This way any little problems that could turn into big problems will present themselves and can be fixed immediately.

 

[waterdog]

That rubber hose appears to be an odd size (~22 mm I believe). A buddy at Goodyear Rubber had a piece of rubber tubing laying around that fit but kinked, so i put a smaller diameter hose inside to keep it from kinking and it seems to work.

 

[Clip]

just watch it close, make sure that it's not going to give any time soon since it isnt the dealer part

 

[castrol supra]

truth!! I get large fuel & oil lines at a industrial hose supplier, they have any and all hoses for industrial use and often the hose size you need they may only have in stock in a rating that cost more than the dealer hose. Mainly good for older cars where there exists no dealer option.

I am so glad someone finally said this.

I have been alone in this sentiment for a very. Long time.

Rebuild. It's always a good idea to rebuild matching # stock parts.

Or your next choice is a period correct swap that you will need to rebuild before plugging and playing.