Considerations when installing a used motor

[mikefocke]

Ok, you have the engine out of the car because it has blown and you sourced a thought-to-be-good replacement engine.

Now you are faced with the age old question of how much preventative maintenance is the right amount and how much is too much. And how much improvement do you want to do?

Since many of these replacements are easier to do with the engine out of the car, what do you replace before you install that used engine? And where do you use OEM parts and where do you use third party "improved" parts? (known third party parts are underlined)

Clutch?

Pressure plate?

AOS/J-tube?

Heat exchanger?

Water Pump? Thermostat? Gasket? Pulleys? Belt?

Head gaskets?

Plugs? Plug wires? Coil packs? Spark Plug Tubes? O-Rings?

IMS?

RMS?

Chain Tensioner?

Drain Plug?

Deep Sump Kit?

Motor Mount?

Fuel-injector O-rings?

What else should you consider replacing/upgrading?

[Steve Tinker]

Put the replacement engine in a crate and send it to Flat6 Innovations for a thorough inspection by a crew who know what to look for.

Sure its going to cost, but in the end, you have a very fast, bullet proof engine that should be good for 200,000 miles.

You can sleep easy and when it comes to resale, the rebuild quality by a pro has to be a plus ........

[txhokie4life]

Ok, you have the engine out of the car because it has blown and you sourced a thought-to-be-good replacement engine.

Now you are faced with the age old question of how much preventative maintenance is the right amount and how much is too much. And how much improvement do you want to do?

Since many of these replacements are easier to do with the engine out of the car, what do you replace before you install that used engine? And where do you use OEM parts and where do you use third party "improved" parts? (known third party parts are underlined)

*** Sorry I originally had quotes and unquotes -- but the post engine didn't like it.

Depends on the age of the donor, how long it has sat.. etc.

With my projects I have used exclusively OEM parts, except for upgrades from LN Engineering

for the IMS and Thermostat.

I take the tact I never want to see a project twice.

In my mind the effort to get an engine in and out is reasonably high and

you already have a pretty good investment in the engine (and the car) itself

so you want to have as "new" an end result as reasonable.

Note my first project was the complete rebuild of a Boxster S -- what is now

my everyday driver and I did all the below and more

(since it was a tear down to the crank) (Jeff at Sunset and I became good buddies)

So I guess I can say I stand behind my words :-)

Clutch?

Pressure plate?

Not specifically engine related -- but I did both at 30k -- while you are in there you're looking

at about $500 for parts and a tad extra labor.

AOS/J-tube?

Yes -- as they generally have been redesigned and upgraded

Heat exchanger?

In most cases this is cheap insurance.

Water Pump? Thermostat? Gasket? Pulleys? Belt?

Yes, Possibly, I like to use the LowTemp Thermo from LN, yes, not usually unless high mileage or issues,although

replacing tensioner pulley is reasonable, almost for sure on the belt.

Head gaskets?

Only if the heads are pulled. Then it is a must.

Plugs? Plug wires? Coil packs? Spark Plug Tubes? O-Rings?

I have done this for every engine I have done -- but may or may not be required.

Technically there are no plug wires.

IMS?

100% of the time for me.

RMS?

Stairing you in the face begging to be done :-) very cheap part

Chain Tensioner?

Not cheap. when you consider there are 3 and each is pricey.

Drain Plug?

Probably not worth it -- but doesn't cost much

Deep Sump Kit?

If you are going to track it -- I think you should seriously consider it -- others might

say it is a must. Otherwise -- probably not needed.

Motor Mount?

I would inspect these and make a call at the time

Fuel-injector O-rings?

If you remove the intake than this is reasonable.

What else should you consider replacing/upgrading?

You've covered a lot of stuff.

Lets assume you are not tearing the engine down.

The oil pump hexoganal stem that comes off the IMS

is reportedly a weak link. The effort to pull the oil pump

off if the engine is out is not that bad. LN? and/or Flat6Innovations

sells an upgrade.

Depending on the age of the engine, I would look at the timing chain tensioner blades

for the cams. I've experienced excessive wear on those.

If you are going to do this -- that means you pulled the cam cover, and then you might as well

check the lifters.

Then you can inspect the valve springs -- and decide if you want a valve job or not.

You get your head gasket that way :-)

I would inspect and replace any suspect hoses.

Possibly do a transmission fluid change/filter as well.

I'm probably forgetting somethings -- but your list was pretty extensive :-)

All this starts to add up as death by a thousand cuts...

No one part or replacement seems to cost all that much,

but when you add them all together -- ouch! :-)

look forward to others thoughts on this thread.

Mike

Edited February 4, 2010 by txhokie4life

[70Sixter]

Well txhokie4life, that was pretty comprehensive!

Not to steal ppbon's line, but Pedro sez the front motor mounts go at 30-40k mikes.

And +1 on Jake's shop in North GA!