Virginia's Block Gets Drilled - By a Failed Water Pump

Dwayne · 08-23-2009, 07:27 PM

You may recall earlier this year I posted a massive picture thread on an intake refresh procedure I performed on this car November-December last year. At the same time, I also performed a TB/WP change and new motor mounts, OPG and oil pan stud kit. Even though the car only had 35K miles on it, I figured the original water pump was 20 years old and it was best to replace it and be set for another 60K miles. I replaced the original with a rebuilt unit with metal impeller.

Everything went fine with the replacement and my wife has been driving the car for about 3000 miles over the last 6 months or so when I recently noticed coolant was low in the reservior. Upon further inspection, I also noticed coolant on the bottom of the engine. The only source I could pinpoint was at the bottom of the front of the engine - on top of the oil pan. The rest of the engine was bone dry.
01-engine.jpg

I figured the leak must be coming from behind the cam/engine covers and was probably from a leaking gasket on the water pump. So I set about taking the front of the engine apart. But first I drained the coolant and noticed it was not exactly bright green. When one of the hoses leaked coolant on my cardboard covering on the floor, I discovered massive amounts of pretty sparkly metal glitter. Funny, I didn't remember adding sparkly metal glitter to the coolant! Here's a picture of a small amount of spillage on the cardboard after it dried.
03-metal-filings.jpg

At this point, I'm thinking something is seriously wrong. After removing the cam covers, I checked the timing belt tension and it was right where I left it after retensioning the new belt earlier this year - right at the upper end of the tension range on the Kempf tool. Could this be too tight I wondered??
02-Belt-Tension.jpg

The source of the leak appears to be near the back side of the WP pulley. You can see the trail of black residue from what appears to be metal filings in the picture. After I got the timing belt off, I noticed the WP pully did not move freely and felt like it was scraping - but on what??
04-leak-source.jpg

When I got the WP off, I found a deep countersunk hole in the block where the impeller mated up.
05-crankcase-1.jpg

Being a Noob, I wasn't sure what to think of the grooves.....
06-crankcase-2.jpg

....but the impeller moved freely when the WP was off the block. Therefore, it had to be rubbing against the block. However, there were no audible clues or unusual running conditions when the engine was running last week.
07-crankcase-3.jpg

I had to compare a picture from when I had the WP off last Nov/Dec to confirm for sure that the impeller had indeed dug into the block. Here's the previous picture of the block when I had it apart Nov/Dec. You can see the WP opening is smooth with no groove cut into it.
07-crankcase-4.jpg

Here's the impeller on the failed WP.
08-impeller-1.jpg

It appears to have moved outward toward the block and began drilling away and neither my wife or I were the wiser.
09-impeller-2.jpg

So now I'm going to replace the WP but this time I think I'll go with a plastic impeller. However, with the damage to the block, I'm assuming that the new WP will not be as efficient as originally designed (i.e., with the new gap between the impeller and block, the pump will not be able to move the same volume of water or have the same pressure as originally designed). Correct??

So, I just happened to read a thread about a possible repair to a block that has been damaged by WP impellers using a newly developed tool. I will look into this next.

Just thought I'd share the latest adventure.

IcemanG17 · 08-23-2009, 07:31 PM

DAMMM DAMMM DAMMM....so the only symptom was a leaking waterpump? No noise or overheating? I would think getting ground like that would cause quite a bit of noise...but I guess the water hid it? Damm...

ROG100 · 08-23-2009, 08:12 PM

We need to know - rebuild, Laso old, Laso new, Porsche rebuild or Porsche new.
Metal impeller means not the latter two.
Maybe a HT.

worf928 · 08-23-2009, 08:26 PM

Quote:

Originally Posted by Dwayne

...However, there were no audible clues or unusual running conditions when the engine was running last week....

Unfortunately, slow machining of the block is a silent death.

Quote:

... I'm assuming that the new WP will not be as efficient as originally designed (i.e., with the new gap between the impeller and block, the pump will not be able to move the same volume of water or have the same pressure as originally designed). Correct??

From the looks of your picture, yes. Have you measured the depth of the damage? It looks like several millimeter and IMO will result in some loss of efficiency.

My condolences. It surely sucks.

IcemanG17 · 08-23-2009, 08:29 PM

Dwayne
I have a spare 87 motor...PM sent

BBX · 08-23-2009, 08:30 PM

Honestly, I think that water pump is defective. It still looks new, it should never have moved like that. I guess it might have been a rebuilt unit and pressing the bearings off and on again might have messed with the tolerances that keep the impeller put. I would call the company and ask them why they are selling water pumps that destroy engines!

Dwayne · 08-23-2009, 08:39 PM

Quote:

Originally Posted by IcemanG17

DAMMM DAMMM DAMMM....so the only symptom was a leaking waterpump? No noise or overheating? I would think getting ground like that would cause quite a bit of noise...but I guess the water hid it? Damm...

Hello Brian,
Now that you mention it, about 4 weeks ago, my wife drove to Lancaster (90 mile trip one way) when it was about 105 degrees, with the A/C running and driving through Red Rock Canyon. She noticed the temperature reached to barely above the 2nd white line. One week later, she made the exact same trip, same temp about 105 degrees, with A/C, through Red Rock Canyon and she said the temp never rose above the mid-way mark between 1st and 2nd white lines (normal). This car has never gotten close to the 2nd white line that I can remember in the last 6 months (since the new WP). I was out of town at the time she made the trips so didn't think anything of it since it didn't repeat. I guess it's possible the impeller was extra hungry that day.....

Quote:

Originally Posted by ROG100

We need to know - rebuild, Laso old, Laso new, Porsche rebuild or Porsche new.
Metal impeller means not the latter two.
Maybe a HT.

Hi Roger,
The failed WP was a Rebuilt unit. I purchased it last November. We should add one more "FAILED" count to the Rebuilt metric.

Bill Ball · 08-23-2009, 08:44 PM

Argh!!! I hate it when that happens.

To paraphrase Betty Davis from Mommie Dearest: NO MORE METAL IMPELLERS!

Not that I like the plastic ones that much better. They appear to come loose more often but the damage they do is limted to overheating, which still destroyed one of our former Big 3's own stroker blocks.

Anyway, I'm sorry to see this, Dwayne. The fact that it failed so quickly argues that this was a badly rebuilt water pump and should never have been sold.

ROG100 · 08-23-2009, 08:48 PM

Rebuild - another bad tick.
So sorry that happened. At least Greg & Steve have a fix.

Lizard931 · 08-23-2009, 08:55 PM

looks to me that the bearing assembly moved inside the aluminum housing.

This is sad to see happen, depending on how deep it was will depend on how much efficency will be lost.

ROG100 · 08-23-2009, 09:02 PM

In theory the company that builds the Porsche rebuild also builds the rebuild.
Lots of companies sell the rebuild which is available at very attractive prices.
Rebuild of rebuild is not good in my book.
The major wholesalers sell the rebuild. So even if the BIG 3 stop selling the rebuild along with 928sRus (big 3 and a half maybe) there are many other companies selling it.
Zims, Vertex, Pelican on and on.

namasgt · 08-23-2009, 09:03 PM

Im so sorry Dwayn. I think Im going to trow my rebiult Laso away and get a new design one, I only used it for about 3 to 4 minutes on the engine.

namasgt · 08-23-2009, 09:06 PM

Quote:

Originally Posted by ROG100

In theory the company that builds the Porsche rebuild also builds the rebuild.
Lots of companies sell the rebuild which is available at very attractive prices.
Rebuild of rebuild is not good in my book.
The major wholesalers sell the rebuild. So even if the BIG 3 stop selling the rebuild along with 928sRus (big 3 and a half maybe) there are many other companies selling it.
Zims, Vertex, Pelican on and on.

okay Im confused, what Rebuild rebuilt are you guys talking about, are you talking about the Rebuilt Lasos ??

ROG100 · 08-23-2009, 09:10 PM

Ali,
All Laso WP's are new. They are rebuilds if someones takes a used Laso, Porsche or HT pump and rebuilds it.
Roger

the flyin' scotsman · 08-23-2009, 09:14 PM

Dwayne............thats just not right. After all your hard work and excellent write up this happens.

You'll now hear a bunch of comments as to what pump you should now use; I went with a 'new' Laso WP from Roger. As well as many other projects, water bridge gaskets etc, the engine is running well and at the before guage readings; between marks 1 and 2.

08-23-2009, 07:27 PM	#1
Dwayne Addict Rennlist Member Join Date: Sep 2007 Location: Ridgecrest, California Posts: 1,292	Virginia's Block Gets Drilled - By a Failed Water Pump You may recall earlier this year I posted a massive picture thread on an intake refresh procedure I performed on this car November-December last year. At the same time, I also performed a TB/WP change and new motor mounts, OPG and oil pan stud kit. Even though the car only had 35K miles on it, I figured the original water pump was 20 years old and it was best to replace it and be set for another 60K miles. I replaced the original with a rebuilt unit with metal impeller. Everything went fine with the replacement and my wife has been driving the car for about 3000 miles over the last 6 months or so when I recently noticed coolant was low in the reservior. Upon further inspection, I also noticed coolant on the bottom of the engine. The only source I could pinpoint was at the bottom of the front of the engine - on top of the oil pan. The rest of the engine was bone dry. 01-engine.jpg I figured the leak must be coming from behind the cam/engine covers and was probably from a leaking gasket on the water pump. So I set about taking the front of the engine apart. But first I drained the coolant and noticed it was not exactly bright green. When one of the hoses leaked coolant on my cardboard covering on the floor, I discovered massive amounts of pretty sparkly metal glitter. Funny, I didn't remember adding sparkly metal glitter to the coolant! Here's a picture of a small amount of spillage on the cardboard after it dried. 03-metal-filings.jpg At this point, I'm thinking something is seriously wrong. After removing the cam covers, I checked the timing belt tension and it was right where I left it after retensioning the new belt earlier this year - right at the upper end of the tension range on the Kempf tool. Could this be too tight I wondered?? 02-Belt-Tension.jpg The source of the leak appears to be near the back side of the WP pulley. You can see the trail of black residue from what appears to be metal filings in the picture. After I got the timing belt off, I noticed the WP pully did not move freely and felt like it was scraping - but on what?? 04-leak-source.jpg When I got the WP off, I found a deep countersunk hole in the block where the impeller mated up. 05-crankcase-1.jpg Being a Noob, I wasn't sure what to think of the grooves..... 06-crankcase-2.jpg ....but the impeller moved freely when the WP was off the block. Therefore, it had to be rubbing against the block. However, there were no audible clues or unusual running conditions when the engine was running last week. 07-crankcase-3.jpg I had to compare a picture from when I had the WP off last Nov/Dec to confirm for sure that the impeller had indeed dug into the block. Here's the previous picture of the block when I had it apart Nov/Dec. You can see the WP opening is smooth with no groove cut into it. 07-crankcase-4.jpg Here's the impeller on the failed WP. 08-impeller-1.jpg It appears to have moved outward toward the block and began drilling away and neither my wife or I were the wiser. 09-impeller-2.jpg So now I'm going to replace the WP but this time I think I'll go with a plastic impeller. However, with the damage to the block, I'm assuming that the new WP will not be as efficient as originally designed (i.e., with the new gap between the impeller and block, the pump will not be able to move the same volume of water or have the same pressure as originally designed). Correct?? So, I just happened to read a thread about a possible repair to a block that has been damaged by WP impellers using a newly developed tool. I will look into this next. Just thought I'd share the latest adventure. __________________ Dwayne 84 928 S, 'California', AT, Black/Tan, 168K miles, retired DD 85 928 S, 'Iris', AT, IrisBlue/Tan, 12K miles, Wife's Baby Shark 86.5 928 S, 'Colorado', 5-Speed, Black/Tan, 137K miles, Belt Failure 87 928 S4, 'Oregon', AT, Black/Linen, 51K miles, No Sunroof!, My DD 87 928 S4, 'Virginia', AT, Cassisrot/Burgundy, 51K miles, No Sunroof!, Wife's DD 88 928 S4, 'Idaho', AT, White/Burgundy, 28K miles, Wife's Pampered Shark Dwayne's Garage: http://dwaynesgarage.norcal928.org/

08-23-2009, 07:31 PM	#2
IcemanG17 Addict Rennlist Member Join Date: Sep 2004 Location: Stockton, CA Posts: 14,056	DAMMM DAMMM DAMMM....so the only symptom was a leaking waterpump? No noise or overheating? I would think getting ground like that would cause quite a bit of noise...but I guess the water hid it? Damm... __________________ "think all cops are bad....try living in a world without them!" Brian Co-founding member of the "Stockton Sharks Society" 79 racer "Casper" 5spd, 242whp 257torque 2719lbs 10 Silverado (tow rig) ---------------------- 84 auto "Estate" racer 215whp 256torque, 2800lbs 08 M3....gone but not forgotten 88 S4 Guards Red/Champagne Leather (gone to a new home) 89 S4 5 speed track beast!!!! BLACK WIDOW (gone..dead)

08-23-2009, 08:12 PM	#3
ROG100 Addict Rennlist Member Rennlist Site Sponsor Join Date: Jan 2003 Location: Double Oak, TX Posts: 9,351	We need to know - rebuild, Laso old, Laso new, Porsche rebuild or Porsche new. Metal impeller means not the latter two. Maybe a HT. __________________

08-23-2009, 08:29 PM	#5
IcemanG17 Addict Rennlist Member Join Date: Sep 2004 Location: Stockton, CA Posts: 14,056	Dwayne I have a spare 87 motor...PM sent __________________ "think all cops are bad....try living in a world without them!" Brian Co-founding member of the "Stockton Sharks Society" 79 racer "Casper" 5spd, 242whp 257torque 2719lbs 10 Silverado (tow rig) ---------------------- 84 auto "Estate" racer 215whp 256torque, 2800lbs 08 M3....gone but not forgotten 88 S4 Guards Red/Champagne Leather (gone to a new home) 89 S4 5 speed track beast!!!! BLACK WIDOW (gone..dead)

08-23-2009, 08:30 PM	#6
BBX Addict Rennlist Member Join Date: May 2009 Location: San Diego, Ca Posts: 1,012	Honestly, I think that water pump is defective. It still looks new, it should never have moved like that. I guess it might have been a rebuilt unit and pressing the bearings off and on again might have messed with the tolerances that keep the impeller put. I would call the company and ask them why they are selling water pumps that destroy engines! __________________ B. B.

08-23-2009, 08:44 PM	#8
Bill Ball Under the Lift Lifetime Rennlist Member Join Date: Mar 2002 Location: Alamo, CA Posts: 16,619	Argh!!! I hate it when that happens. To paraphrase Betty Davis from Mommie Dearest: NO MORE METAL IMPELLERS! Not that I like the plastic ones that much better. They appear to come loose more often but the damage they do is limted to overheating, which still destroyed one of our former Big 3's own stroker blocks. Anyway, I'm sorry to see this, Dwayne. The fact that it failed so quickly argues that this was a badly rebuilt water pump and should never have been sold. __________________ Bill GP White '89 S4 - 242K carefree (well, almost) miles SLC Motosport X-pipe - 928 Specialists RMB - '87 rear resonators - '83 LSD - Performance Shock, Inc. double-adjustable Konis with main/tender Eibachs - 2002 996 wheels - Momo Club 3 steering wheel - H4 HID headlights Sharks in the Park XII, May 5, 2012 - Tilden Park, Berkeley, CA. - Pictures courtesy fo George Suennen. If you live in North or Central CA, join our group at Norcal928.org

08-23-2009, 08:48 PM	#9
ROG100 Addict Rennlist Member Rennlist Site Sponsor Join Date: Jan 2003 Location: Double Oak, TX Posts: 9,351	Rebuild - another bad tick. So sorry that happened. At least Greg & Steve have a fix. __________________

08-23-2009, 08:55 PM	#10
Lizard931 Addict Rennlist Member Join Date: Apr 2003 Location: Abbotsford B.C. Posts: 7,135	looks to me that the bearing assembly moved inside the aluminum housing. This is sad to see happen, depending on how deep it was will depend on how much efficency will be lost. __________________ Colin J 1981 928S Euro, 1987 928S4 Auto 1987 928S4 5 speed Koni 1000/600, Stage II cams, Aluminum flywheel, dual disc Stage 3+ Spec clutch, Crankcase vacuum pump, CT4 6767 custom mid mount turbo @ 5.8PSI 408/400+, Really loud horn! PM me for services/parts.

08-23-2009, 09:02 PM	#11
ROG100 Addict Rennlist Member Rennlist Site Sponsor Join Date: Jan 2003 Location: Double Oak, TX Posts: 9,351	In theory the company that builds the Porsche rebuild also builds the rebuild. Lots of companies sell the rebuild which is available at very attractive prices. Rebuild of rebuild is not good in my book. The major wholesalers sell the rebuild. So even if the BIG 3 stop selling the rebuild along with 928sRus (big 3 and a half maybe) there are many other companies selling it. Zims, Vertex, Pelican on and on. __________________

08-23-2009, 09:03 PM	#12
namasgt User Join Date: Nov 2008 Location: Arlington Texas Posts: 1,125	Im so sorry Dwayn. I think Im going to trow my rebiult Laso away and get a new design one, I only used it for about 3 to 4 minutes on the engine.

08-23-2009, 09:10 PM	#14
ROG100 Addict Rennlist Member Rennlist Site Sponsor Join Date: Jan 2003 Location: Double Oak, TX Posts: 9,351	Ali, All Laso WP's are new. They are rebuilds if someones takes a used Laso, Porsche or HT pump and rebuilds it. Roger __________________

08-23-2009, 09:14 PM	#15
the flyin' scotsman Addict Rennlist Member Join Date: Oct 2004 Location: Southern Alberta, Canada Posts: 7,718	Dwayne............thats just not right. After all your hard work and excellent write up this happens. You'll now hear a bunch of comments as to what pump you should now use; I went with a 'new' Laso WP from Roger. As well as many other projects, water bridge gaskets etc, the engine is running well and at the before guage readings; between marks 1 and 2. __________________ Malcolm '93 GTS 5 speed Polar Silver/Linen, 154k kms '88 928 S4 A/T Black/Ivory, 186k kms 928OC Trustee avatar: GTS at start/finish line Circuit Gilles Villeneuve, Montreal, Canada

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