thoughts on remanufactured engines

[45Auto]

Re: thoughts on remanufactured engines

Ever been in a $1500 rebuild?

It would appear that you've never been in a rebuild OR factory engine.

The factory clearances are usually perfect.

If you define "perfect" as within specs, you are correct. But so is the $1500 rebuild.

Lifters are mated in batches measured to the 0.0001th.

Exactly what dimension on a lifter do you imagine is measured to a ten thousandth? And why would it be?

Engine balance is perfect.

Hopefully you really aren't that naive.

Every manufactured product is built to as wide a tolerance as possible given it's operating requirements. There's a range of acceptable dimensions. It's actually very simple to rebuild an engine to much better than factory tolerances.

Given that I can buy a BRAND NEW Goodwrench crate long block for $1800, exactly how much care do you imagine that the factory puts into them?

http://www.summitracing.com/parts/NAL-12568758

The big rebuilders use the EXACT same equipment as the factories, but the cost percentage of the $1500 rebuild devoted to "finish" machining (boring, align honing, etc) is much higher than on the factory engine. GM has to do ALL the machining (oil galleries, combustion chambers, freeze plugs, tapped holes, crank journals, etc) from the RAW castings, while all the rebuilder has to do is bring the finish machining back into tolerance.

Since you obviously have no idea what goes into a rebuild, here's some pics for you from Rapido Marine.

http://www.rapidomarine.com/

I even added a big red arrow to point out the new valve springs for you since that seemed to be a big concern of yours (maybe they bend the old ones so bad taking them off with your hammer that they have to use new ones!) - even though my 23 year old factory valve springs still deliver the same performance as when the boat was new.

$1450 5.7L GM longblock:

Component view (look for the red arrow!):

 

[Howard Sterndrive]

Re: thoughts on remanufactured engines

I rebuilt engines for a living in a Caterpillar reman shop. We did excellent work and had few comebacks. Everything was dyno'd under load before ship. We lost the odd one on the dyno but very few in the customer's hands.
Several of the guys I worked with had experience at automotive rebuild shops. From hearing the horror stories of how those places make profit, I would never buy a reman gas engine.
I'd buy new for the measly $500 extra. (a couple tank$ of fuel)

New Chevrolet 350 Crate 290HP (looks to be identical to marine specs of the mid 1980's except for core plugs- has 2 pc rear main perfect for the vintage boat- especially for the OMC stringer crowd that have no coupler avail for 1 pc.)
around $1950 at Summit. You sacrifice the warranty putting it in a boat, but heck...it's new..... run it on a stand for a few hours..watch oil pressure. Factory new is the way to go AFAIC.

 

[HT32BSX115]

Re: thoughts on remanufactured engines

Engine balance is perfect.

I think I have to disagree with that.

I know a few people that balance engines for a living and more than a few of them have told me that factory balance is never more than adequate.

They don't balance the engines at all. They just put them together.

They're at the mercy of the parts manufacturers.

The only way to balance an engine IS TO BALANCE the engine...........every one of them...... OEMs don't do that.

 

[Fun Times]

Re: thoughts on remanufactured engines

Take a look at these mercury videos, This may help with a buying decision process.

http://sites.mercurymarine.com/portal/page?_pageid=33,82238&_dad=portal&_schema=PORTAL

Good luck with it.

 

[Aloysius]

Re: thoughts on remanufactured engines

45, If you have to ask "what dimension" then you really don't know.

Balance..basically unimportant under 5000 rpms. In GM's case, they weight match pistons, rods are PM so they all automatically weigh the same, flywheel is balanced, crank is balanced. Balancing is a compromise anyway...just how much of the rod is reciprocating and how much is rotating? How much bobweight do you really need to use?

Just noticed..proper crank balance is done with the flywheel and damper attached. Balancing the crank without these items is just marketing hype.

"clevite" bearings..not necessarily Clevite 77.

New pistons and parts..Rebuilder quality I presume.

"Line bore"..generally unnecessary, and can be detrimental. Reduces center to center distance on the cam and crank. Some engines (Honda for instance) use select fit bearings to achieve proper alignment.

I have physically rebuilt dozens of engines, many for racing. People like Howard above have obviously performed similar high quality work..Diesels that are under 100% load most of the time must also be perfect. The end product is only as good as the person doing the work.

"quality control" is the key.

 

[Philster]

Re: thoughts on remanufactured engines

Actually, it'd be foolish to make sweeping statements either way.

There are crap OEM engines littering the waters, and there are great ones, too. There are crap reman engines littering the waters, and great ones, too.

Depending on who your engine builder is, you could out-gun an OEM piece. Remans often make financial sense. Depends on engine size, block availability and many other factors. Some new engines cost over 10g's, while a rebuild is about 70% of that, and you could add a few goodies that OEM won't.

Not so sure anyone can make blanket statements here.

 

[tonyrocks]

Re: thoughts on remanufactured engines

Thanks for all the replies, everyone. Its always nice to have as much info/knowledge as possible if I go down that road.

Appreciated.

 

[MCL]

Re: thoughts on remanufactured engines

When I needed a new engine I first contacted rapido marine.Ive heard great things about them but the customer service sucked.

I ended up ordering the engine from marineengine4less,a bit more expensive but the customer service was suberb until payment.After that any questions were answered with 1 sentence if at all.The engine showed up with the carb missing,no papers about anything,no plugs or covers on sparkplug holes,exhaust or oil filter.They changed their story every day,blamed it on shipping.Kinda weird that the carb got lost since it arrived in a sealed crate in a sealed container which was loaded 100 miles from the builder.I didnt have any leverage in the matter as im in Finland and the builder refused to take any responsibility.

I cant blame the builder for sure.But the fact that it was shipped 100miles(which the builder arranged) to a acquaintance of my who loaded it onto the container.And then it arrives still in a sealed crate.I quess everyone can do the math.Cant say anything about build quality as I dont have the money for the carb,the warranty will run out before I ever get a chance to run the engine.

 

[Aloysius]

Re: thoughts on remanufactured engines

I've never seen a rebuild come with a carburetor...they rarely even come with an intake manifold. Oil pans are often application specific also, along with the oil pick-up.