GregBBRD

Yes, material removal is needed...although the loose impeller does a pretty good job. I had a big cutter made that cuts a smooth surface for the tool and insert to sit on.

JWise

Pretty amazing what can be done with a good 5-axis machine. I have a customer who makes replacement parts for Boeing 737s with one.

ew928

What sort of metal is the insert?
Probably not semi-ferrous as it will probably rust.
Just wondering if flakes/shards of it can be picked up with magnetic probe into the coolant.

Just thinking out loud.

blown 87

Is this tool based on a water pump housing?
You might want to think about selling the rights to that to Baum, AST, OTC or some other special tool company.

It is neat stuff, bet it was not cheap to have all that done either.

James Bailey

You never cease to amaze me with your skills and determination to do it RIGHT ....Well done !

svp928

Greg and Dave came up with the idea, if I recall, and I just volunteered to make the tool as "donation" to the Save a 928 Foundation....Greg actually had the cutter made at his own expense, and it works well. It fits in a waterpump housing, and he has a collar to set how deep it cuts. We made inserts in several different thicknesses, so you don't have to remove any more material than necessary.
So, you bolt the cutter/housing on the block, then set the depth collar so you only take off enough material to clean up. Remove cutter/housing, then attach the tool we made. Drill though the guide bushings, then remove and replace them with the tap-size bushings, and tap the holes you just drilled, then remove the tool and bolt on the insert.
Boom! Done.
Install new waterpump and away you go. Much easier than a new block!

Thanks to Greg and Dave for the idea, and glad I could help.

svp928

Perhaps a little more explanation on the tool is helpful- the knurled bushings in the pics are called "slip-fit drill bushings". If you look closely, you will see that the side of the bushing is machined away and has a step at the bottom. The small bolt next to each bushing holds it place. To remove a bushing, you just loosen the bolt, turn the bushing 90deg so the cut aligns with the bolt, and it slips out of the hole. This way, you have two sets of bushings- one for the drill size, and one for the tap size. They can be swapped in place in about a minute, and you don't have to remove the tool till you are done. Nice and easy!

Mike Frye

Brilliant! Very well thought out.

So could this be done on an engine in the car or do you have to pull the engine, do the work and completely clean out all of the filings before putting it all back together?

ROG100

Gregg & Steve - great work!
Now all we need is a water pump that does not fail.

GregBBRD

All of the pieces are designed to allow this to be done while the engine is in the car...we're going to find out, this week.

Landseer

Nice innovation! More preservation is now possible.

svp928

Roger, I backed off on the waterpump itself, because other folks are working on it and were going to have something soon... I haven't heard anything lately. As near as I can tell, it would cost about what a high-end Chevy billet pump costs, and have very similar parts inside it.

Anything else you want made?

Dwayne

Hello Greg,
I just took my WP off today (on the '87) and discovered a drilled block/failed impeller. I'm very interested in the new tool you describe here. Sounds like you are testing it on the first block next week? If successful, would my block be a candidate for using the tool?? Here's one of the pics (you can see more on the thread titled, "Virginia's block gets drilled - by a failed water pump"). THANKS!

svp928

Dwayne, thats exactly what its for- we'll see how Greg's experiment comes out.

GregBBRD

Yup, you have the disease we're trying to cure.

That's why we went to all this trouble. I had a "hand built" insert I could have stuffed into the block I'm working on 6 weeks ago. Steve and I "donated" our time for the "betterment" of the 928 community. Mark Anderson donated a couple water pump "cores" to make the fixture to hold the pump and a couple of impellers, to get angles from. Steve needs to recover the costs of building inserts (current and future ones) and I'd like to get my $800.00 tool paid for.