engine thrust bearing repair

88porsche928 · 11-04-2009, 05:30 PM

is their any repair for engine thrust bearing failure? or is the entire engine garbage?

blown 87 · 11-04-2009, 05:58 PM

If it got into the block it is done.

Xlot · 11-04-2009, 06:04 PM

uh oh.. this doesn't bode well.

There are a couple of posts here about repairing blocks that have have thrust bearing failure.

Someone (I think Imoo?) mentioned a Candaian 928 that had a repair done by machining out the damaged part and using an insert?

However, probably much $$ compared to just getting a new engine (warning: make sure the engine is good - that means buying from someone who will warranty it, not just someone who says "ran great when I pulled it")

mark kibort · 11-04-2009, 06:06 PM

doesnt this mean that the thust bearing is damaged? cant you just replace the thrust bearing, and check the crank to see if it is damaged as well?

Imo000 · 11-04-2009, 06:08 PM

Quote:

Originally Posted by blown 87

If it got into the block it is done.

That’s not so.

As long as the block isn’t cracked it’s fixable but it won’t be cheap or easy. I’ve seen one repaired and it worked flawlessly. The damaged area was machines flat and a 2 piece spacer was installed behind a new (early 32V) thrust bearing. Apparently the early thrust bearings have a larger surface area and are better over all, especially for a repair like this.

blown 87 · 11-04-2009, 06:21 PM

If you say so, but I would never trust a block that the crank had gotten into.
By the time you spent all the money for machine shop stuff, you might just have more money into a questionable block than a good used short block would be.

Quote:

Originally Posted by Imo000

That’s not so.

As long as the block isn’t cracked it’s fixable but it won’t be cheap or easy. I’ve seen one repaired and it worked flawlessly. The damaged area was machines flat and a 2 piece spacer was installed behind a new (early 32V) thrust bearing. Apparently the early thrust bearings have a larger surface area and are better over all, especially for a repair like this.

cali4sun · 11-04-2009, 06:23 PM

Just had my flex plate checked recently wanted to avoid this scenario....Best of luck on repair!

'89 S4 GP White/Black
'76 912E Silver/Black sunroof

Imo000 · 11-04-2009, 06:38 PM

Quote:

Originally Posted by blown 87

If you say so, but I would never trust a block that the crank had gotten into.
By the time you spent all the money for machine shop stuff, you might just have more money into a questionable block than a good used short block would be.

If you do all the work, besides the machining, the cost of maching is not that much (3-4hrs). They only have to touch one side of the journal. I have no reason to beleive that it will not be as stong as it was before. AND at the end, you'll have an engine that has all new gaskets too. If you buy a good used engine, the gaskets will probalby be old so you would want to re seal it anyways and that will add at least $350 to the cost.

The original question was if it's fixable and I'm saying it is. Is it practical or cost effective, well that depends but it certainly is doable.

G Man · 11-04-2009, 07:15 PM

Aw heck...just smear a bunch of JB weld over the damaged part of the block and jam a new thrust bearing in there before it sets up and you'll be good to go!

blown 87 · 11-04-2009, 07:24 PM

Don't they usually crack really bad when this happens?
Most of them I have seen do.

I will say that you may be right, on some blocks it may be possible to save them, I am just not going to do it.

And, you are also right, that was not his question.

Quote:

Originally Posted by Imo000

If you do all the work, besides the machining, the cost of maching is not that much (3-4hrs). They only have to touch one side of the journal. I have no reason to beleive that it will not be as stong as it was before. AND at the end, you'll have an engine that has all new gaskets too. If you buy a good used engine, the gaskets will probalby be old so you would want to re seal it anyways and that will add at least $350 to the cost.

The original question was if it's fixable and I'm saying it is. Is it practical or cost effective, well that depends but it certainly is doable.

Tom928 · 11-04-2009, 07:38 PM

My $0.02 worth.

Even if it were fixable - reliability would be something I would be very concerned with. I have thought of what I would do in this situation and decided if it did, I would buy a used engine and rebuild it.
Others may disagree, but I would not want to worry about how reliable the fix would be.

Good Luck,

docmirror · 11-04-2009, 07:50 PM

We're not sure yet it's TBF. It could be 2/6 rod bearing. The engine is seized hard. Need to get into the crankcase to find out for sure. I wonder if there's a way to snake a borescope down the oil filler area after removing the baffle to inspect the crank thrust webbing?

soontobered84 · 11-04-2009, 07:59 PM

Someone local Doc?

blown 87 · 11-04-2009, 08:46 PM

Quote:

Originally Posted by docmirror

We're not sure yet it's TBF. It could be 2/6 rod bearing. The engine is seized hard. Need to get into the crankcase to find out for sure. I wonder if there's a way to snake a borescope down the oil filler area after removing the baffle to inspect the crank thrust webbing?

I think I could get mine in through the oil drain and be able to see it, but I have never tried to.

I have a 928 in the shop and it is getting a oil change tomorrow, if my dumb ass does not forget, I will try to see if I can see the rear of the thrust bearing area.

I will post a pic in a minute of the one I have.

88porsche928 · 11-04-2009, 10:24 PM

i wasnt driving it hard and the rpms went high i dont know how it happened. heres what happen one day i got the water pump and timming belt changed shortly after I changed the oil/filter. next day after i brought the car back it started cutting off at low rpm / at stop lights. while driving back to the mechanic the car died without making any sounds on the interstate, i was driving slow but the rpms where above 1,000. I could not start the engine becuase the battery was drained again, I told the mechanic to drop the oil pan and also check out the thrust bearings, what else should I ask him? I took this car to performance independant porsche in san diego, the guy has alot of experience with porsches and has no complaints against him. he said he doesnt know what could have caused it.

11-04-2009, 05:30 PM	#1
88porsche928 User Join Date: Sep 2007 Posts: 164	engine thrust bearing repair is their any repair for engine thrust bearing failure? or is the entire engine garbage?

11-04-2009, 06:04 PM	#3
Xlot Addict Rennlist Member Join Date: Jun 2006 Location: Sydney, Down Under Posts: 1,161	uh oh.. this doesn't bode well. There are a couple of posts here about repairing blocks that have have thrust bearing failure. Someone (I think Imoo?) mentioned a Candaian 928 that had a repair done by machining out the damaged part and using an insert? However, probably much $$ compared to just getting a new engine (warning: make sure the engine is good - that means buying from someone who will warranty it, not just someone who says "ran great when I pulled it") __________________ Hilton '89 S4 5-speed - Guards Red, sunroofless - 156k miles '87 S4 5-speed - Grand Prix White, LSD, flip-up wing - 118k miles

11-04-2009, 06:06 PM	#4
mark kibort Addict Rennlist Member Join Date: Feb 2003 Location: saratoga, ca Posts: 14,339	doesnt this mean that the thust bearing is damaged? cant you just replace the thrust bearing, and check the crank to see if it is damaged as well? __________________ Mark Kibort Al Holbert -928Intl. Porsche 928S4 #19 X-Speed GT World Challenge '01,'02,'03,'04 http://video.google.com/videoplay?do...67&q=928+video Laguna Seca SCCA ITE race with Comp Coupe Viper http://www.youtube.com/v/Sih48Dby9d0 TV Highlights http://videos.streetfire.net/video/5...bdf5891242.htm viper race http://video.google.com/videoplay?do...55778690778093 HP vs Torque: http://forums.rennlist.com/rennforum...5-post246.html

11-04-2009, 07:15 PM	#9
G Man Addict Rennlist Member Join Date: Aug 2002 Posts: 2,056	Aw heck...just smear a bunch of JB weld over the damaged part of the block and jam a new thrust bearing in there before it sets up and you'll be good to go! __________________ Jim G Carson City NV 84' 928 auto

11-04-2009, 07:38 PM	#11
Tom928 Addict Rennlist Member Join Date: Jan 2006 Posts: 447	My $0.02 worth. Even if it were fixable - reliability would be something I would be very concerned with. I have thought of what I would do in this situation and decided if it did, I would buy a used engine and rebuild it. Others may disagree, but I would not want to worry about how reliable the fix would be. Good Luck, __________________ Tom '81 928 AT / Guards Red / Black leather '84 928S AT / Kiln Red / Tan - Torque Tube / Trans R&R in progress ....

11-04-2009, 05:58 PM	#2
blown 87 Addict Rennlist Member Join Date: May 2006 Location: Bird lover in Sharpsburg Georgia Posts: 3,185	If it got into the block it is done.

11-04-2009, 06:23 PM	#7
cali4sun User Join Date: May 2009 Location: Pismo Beach, CA Posts: 116	Just had my flex plate checked recently wanted to avoid this scenario....Best of luck on repair! '89 S4 GP White/Black '76 912E Silver/Black sunroof

11-04-2009, 07:50 PM	#12
docmirror Shameful Thread Killer Rennlist Member Join Date: Aug 2004 Location: Ah Luv Ewe, Foat Wuth, Teyxas! Posts: 5,542	We're not sure yet it's TBF. It could be 2/6 rod bearing. The engine is seized hard. Need to get into the crankcase to find out for sure. I wonder if there's a way to snake a borescope down the oil filler area after removing the baffle to inspect the crank thrust webbing? __________________ Doc 90GT, red/tan. FIXED - thx Sean! 86.5, red/blk. I'm just a 'Pabst swilling unibrow'. You know Doc? Sometimes when you post you seem like the BIGGEST prick I have ever had the (un)fortunate opportunity to read from. Brendan Advice or expressions provided by me are for entertainment purposes only. Nothing here is to be used as professional, or legally binding authority by any persons or businesses. I reserve the right to alter, revise, or delete any statements at any time.

11-04-2009, 07:59 PM	#13
soontobered84 Addict Rennlist Member Join Date: Mar 2002 Location: Texas Posts: 1,405	Someone local Doc? __________________ John Curry (Drift King) 928OC member Grand Prix White 1994 GTS AT Cobalt Blue 1989 S4 AT Grand Prix White 1988 S4 AT Indishrot Red 1984 Euro S AT (The Stepson) Black Metallic 1984 Euro S 5 speed (The Schwartz) Rauchquarzmetallic 1983 US version AT (SOLD) Oakgrun 1980 5 speed Euro (The Jalapeno) Pre paint and for sale now

11-04-2009, 10:24 PM	#15
88porsche928 User Join Date: Sep 2007 Posts: 164	i wasnt driving it hard and the rpms went high i dont know how it happened. heres what happen one day i got the water pump and timming belt changed shortly after I changed the oil/filter. next day after i brought the car back it started cutting off at low rpm / at stop lights. while driving back to the mechanic the car died without making any sounds on the interstate, i was driving slow but the rpms where above 1,000. I could not start the engine becuase the battery was drained again, I told the mechanic to drop the oil pan and also check out the thrust bearings, what else should I ask him? I took this car to performance independant porsche in san diego, the guy has alot of experience with porsches and has no complaints against him. he said he doesnt know what could have caused it.