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Index > Engine/Drivetrain > Thread: Cost of rebuild
Thread: Cost of rebuild
Rotary_Pickup


Hauling
Posts: 117
posted April 04, 2004 05:11 PM

Cost of rebuild

I'm considering a rebuild on my engine. I'd like to know, at a minimum, the parts I need to replace. This is under the assumption that there are no broken parts and all are within tolerance. Also, what are the best sources for the parts?

I've never done a rebuild but feel confident, with the right tools, that I can do this. I have replaced rotary engines before and feel I can do it in my sleep.

       
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nwaco


Redlining
Posts: 407
posted April 04, 2004 07:50 PM

If the parts are all within tolerance......

Then rebuilding takes but time, effort and a gasket set including O-rings and sealant. Taking it down is the easy part, cleaning is the hard part and putting it all back together and installing is the fun part.

Beware though, as many as I've done, there are always suprises, and almost always a disapointment or two as well. Don't let it discourage you though, it is still very rewarding and almost always a learning experience.

Cost...if no parts but the minimum are needed, maybe a few hundred plus.

enjoy....


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rotormunky


Redlining
Orlando, Florida
Posts: 424
posted April 04, 2004 09:29 PM

Anyone can feel free to express disagreement with me on the subject, but for the life of me I can't understand why someone is going to pull an engine, tear it down completely, go through all the hassle of reassembling it the right way to all the correct tolerances, and not replaces all the seals and springs while you're there.

Personally I can't recommend doing something half-assed to save $400 now, when you'll probably wind up having to spend more again later.

You should be able to replace everything (assuming your housings are in good shape for under $1,000. Just doing some parts is like pulling a small block and replacing just one rod bearing.

More than likely, you'll be back for the others sooner rather than later.


____________
-Martin
Orlando, Florida

http://www.themonkeyhouse.org/REPU

'77 REPU (Some assembly required :)
'91 Cabrio (Battered and bruised, but she's still my baby.)

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nwaco


Redlining
Posts: 407
posted April 04, 2004 10:00 PM

Maybe I misunderstand your statement Martin......

but, removing a smoky engine and doing a basic rebuild to renew is not exactly a hassle or necessarily "half-assed" to use your terms.

Removing an engine and performing a basic clean and rebuild including a nice coat of paint is but a couple of relaxed part time days of enjoyment. As I mentioned, your probably always in for a disapointment, by means of a few problematic parts that are not within tolerance, but replacing apex's for the sake of just getting new ones without a housing change or compelling need is many a time but an exercise in spending money. I feel that unless you have or are building a high performance engine for use as such, if the seals and housings are good and seated, changing one without the other leads to a situation where you are just as at risk of losing both.

I have found that many a time on an engine that smokes and is a bit lacking on compression, a renewal of oil rings, a good scrubbing of carbon, cleaning up the springs, seals and other parts, and reassembly brings many more fun miles with little to no cost. I find no hassle in doing such.

I have done that with sevens for years, and I found that swapping out engines every now and again has left me spoiled in that I have learned alot, and never lost a seal yet....knock on wood.

Now high performance engines...their another story.

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Jeff20B


Moderator
Posts: 661
posted April 04, 2004 10:52 PM

I agree with nwaco.
____________
'74 REPU
'76 Cosmo
'77 MG Midget 13B
'81 RX-7

       
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rotormunky


Redlining
Orlando, Florida
Posts: 424
posted April 05, 2004 12:08 AM

That's sorta why I left it open to disagreement, I don't yet have any rebuild experience with anything other than piston engines.

If there are possible problems related to replacing apex seals without replacing housings then that's a good point, I'd just never heard about them before now.

I've seen ppl tear down small blocks to replace a spun bearing, and they leave the others in because they pass visual inspection and sometimes something else goes wrong before they have another bearing failure, sometimes not. My thought on the subject is that its soemthing like $800 for a full rebuild kit bought here through a local shop.

For some people the pulling of the engine and tearing it down isn't routine. They might do it once, twice, three times in their life. In my position for instance, the engine is out for the rebuild of the truck. The truck ran without smoke before being decomissioned. I want it cleaned and rebuilt to new specs because that's how I'm doing the whole truck. What I don't want is a part that passed visual inspection to wear out or fail and for me to have to repull the engine tear it back down, replace the part, anything else that failure may have damaged etc.

Personally I hope that this will be the only time the engine is ever out of my truck.

It might be diff if I just rebuilt it, and have an o-ring crap on me and had to tear it back down. But for the extra couple bucks I think I'd rather have all new internals. Unlike you guys I don't have 50 engines in various states of disassembly either :) So you know, we're probably coming from different places.

If I have to tear apart the bottom end of a boinger I'm doing rings while I'm there cause its a couple bucks extra. If I'm doing a timing belt on the grocery-getter, I'm doing a water pump too. While I'm a tinkerer I do everything I can to prevent having to do something twice. Its probably overkill, and the question *WAS* how to do it cheaply so sure you're right on. Just giving another perspective. If replacing seals/springs w/o new housings is a problem (I wouldn't know) then you're right, otherwise I'd rather spend the extra money and have all new parts so I don't have to fix something else next year or the year after. I'd like to think I could get at least 150k w/o a teardown unless its a race motor.



____________
-Martin
Orlando, Florida

http://www.themonkeyhouse.org/REPU

'77 REPU (Some assembly required :)
'91 Cabrio (Battered and bruised, but she's still my baby.)

        Click here to visit rotormunky's homepage. 
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Rotary_Pickup


Hauling
Posts: 117
posted April 05, 2004 08:25 AM

I purchased my 1977 REPU in January 2004 to do a complete rebuild from the ground up. I'm not ready for it financially, so I thought I would rebuild the carb and engine and run it for a couple of years. I plan on dropping in a 3rd gen turbo engine during the ground up restoration.

       
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rotormunky


Redlining
Orlando, Florida
Posts: 424
posted April 05, 2004 08:48 AM

If you can do that, more power to you. Mine was in boxes when I got it as the PO sort of got in over his head and went nuts with no real plan.

If mine were driveable I would have driven it for at least a few months for fun. There are a couple guys that are looking to do a REW install, and you might find a little support if you guys stick together :)


____________
-Martin
Orlando, Florida

http://www.themonkeyhouse.org/REPU

'77 REPU (Some assembly required :)
'91 Cabrio (Battered and bruised, but she's still my baby.)

        Click here to visit rotormunky's homepage. 
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