Preemptive engine rebuild ?
05-24-13, 11:44 AM
#1
Preemptive engine rebuild ?
Is it a good or bad idea to pull out the engine and rebuild it just due to the age? I know there are a lot of rubber seals and maybe some other bits that have a limited life. Depending on the cost I think I'd rather "re-fresh" the engine now rather than deal with the consequences if something important lets go and does real damage to what I think is a very good engine. I have never had any problems and I tend to be on the over-careful side of things so I come up with questions like this.
My car runs great, starts and idles very well. The engine pulls 16" of vacuum (warmed up) at a low idle, it looks like 650-750 rpm. It had good compression before I installed a water injection system so maybe compression is slightly better now. The car has 43k on the original engine and it's basically stock aside from the minor modifications listed in my signature. Maximum boost is 11-11.5 and it tapers off at the high end because I drilled the wastegate pill very slightly. The oil has been changed every 2000 miles or less since 1995 with GTX.
My car runs great, starts and idles very well. The engine pulls 16" of vacuum (warmed up) at a low idle, it looks like 650-750 rpm. It had good compression before I installed a water injection system so maybe compression is slightly better now. The car has 43k on the original engine and it's basically stock aside from the minor modifications listed in my signature. Maximum boost is 11-11.5 and it tapers off at the high end because I drilled the wastegate pill very slightly. The oil has been changed every 2000 miles or less since 1995 with GTX.
05-24-13, 12:36 PM
#3
I'm going to go on the otherside of this.. and say.. I dont know My motor Pulled 18inches at 850 rpm's
before it blew... LoL , But that was because of lack of oil pressure not really seals .
but I wish i had rebuilt it sooner and fixed the issue . rather then it blowing 1000 miles from home ..
BUT like mentioned above... if i had hte money and the choice I'd get a second short block , andstart building it the way you want.
before it blew... LoL , But that was because of lack of oil pressure not really seals .
but I wish i had rebuilt it sooner and fixed the issue . rather then it blowing 1000 miles from home ..
BUT like mentioned above... if i had hte money and the choice I'd get a second short block , andstart building it the way you want.
05-26-13, 01:03 PM
#5
Recovering Miataholic
IMHO, ^+1. We are at 107K miles on original engine and it's smooth and quiet. No usage of coolant, oil is used at about the right rate. Castrol GTX 10W-30 every 3K miles since new. Driven moderately. Idle set to about 720 rpm, and steady at that speed when warm. If anyone is nervous about an aging rotary, 'tis I... but it ain't broke yet!
05-26-13, 01:35 PM
#6
I totaly disagree with leaving it alone. You and others need to understand that at that mileage, the top piece of the stock 3-piece apex seal gets very brittle and can and will break at any moment at your higher than stock boost levels. I also had an original engine last 108k till the rear rotor blew at a slight overboost. Slight meaning it hit 12psi after the double throttle opened.
When I pulled my engine apart, all the non blown parts were perfect and could have easily gone another 100k based on wear alone. At your current state all you will really need to do is soft seals and new apex seals to greatly extend the life of your engine. Dont cost yourself with replacing a rotor and housing by not refreshing the engine now while you can.
When I pulled my engine apart, all the non blown parts were perfect and could have easily gone another 100k based on wear alone. At your current state all you will really need to do is soft seals and new apex seals to greatly extend the life of your engine. Dont cost yourself with replacing a rotor and housing by not refreshing the engine now while you can.
05-26-13, 02:23 PM
#7
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you wouldn't be the first one to pull the engine apart before it was completely dead, it actually makes sense if there are a bunch of oil leaks, and or it needs a clutch or something
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05-27-13, 05:19 AM
#9
Cared for and driven like an adult, I think statistically the overwhelming likelyhood is that a coolant seal will eventually fail in your engine. But probably not until around a 100k if kept near stock power levels. Maybe longer for you since you have an AI system. A coolant seal, if fixed in a timely manner, does no real harm to anything. Then it will make sense to "re-fresh".
05-28-13, 08:00 AM
#12
Original Gangster/Rotary!
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I'd leave it be.
Keep tabs on the cooling system via something like this:
Service Equipment | A/C Service | Robinair Coolant Test Strips - 50 Strips | B207300 - GlobalIndustrial.com
Flush the coolant regularly, and avoid running it overly hot at all costs.
Enjoy the engine. You don't have an expensive turbo bolted to the block, and eventually IMO you'll want to start fresh anyway. Hell, this one may make it to 143k miles
Keep tabs on the cooling system via something like this:
Service Equipment | A/C Service | Robinair Coolant Test Strips - 50 Strips | B207300 - GlobalIndustrial.com
Flush the coolant regularly, and avoid running it overly hot at all costs.
Enjoy the engine. You don't have an expensive turbo bolted to the block, and eventually IMO you'll want to start fresh anyway. Hell, this one may make it to 143k miles
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