grove cutting tool

this is another of those sometimes I hate it when I am always right things.
The whole reason I made my transmission jack was to change a rear main seal on a friends Mack truck
I had been telling him for a year or more that he had an iol leack between the flywheel housing and the engine block.
Every Mack service center in country that he has had some repairs done on his truck while out on the road has said the rear main seal was leaking.
Finally he took it to a shop to get another related issue taken care of on the transmission they kept the truck for 2 weeks then claimed the only thing wrong was the throw out bearing was dry and greased it. The issue was the clutch arm bushings were worn They were supposed to pull the transmission and replace them but they didn't Saying OH they are not bad enough to need replacing at this time
Anyway I told him that if I was to drop the tranny I wanted to replace the clutch since he had 400,000 miles on it already. and I was not going to do a job twice.
He said he wanted the rear main seal replaced anyway OF COARSE YOU DO I thought. And I'm going to have the flywheel ground as well and pull the housing off to FIX the leak
In all the years that truck manufactures have been in business they still haven't learned that when they assemble the flywheel housing to the engine the only thing that keeps the oil from leaking is a microscopically thin layer of RTV sealant. and when the housing is tightened to the block most of that is squeezed out and over time what little that is still there will deteriorate Either the bolts will become loosened slightly from the constant pounding form the torque of the engine or heat and cooling what ever, eventually it is going to leak. because the main sealing is not between the mated surfaces but the tiny little bead of sealant that forms along the edges
The solution that I have done to every housing I have installed for the past 45 or 50 years I learned from my dad long before that. Back when the housings were made of cast iron before RTV was ever invented
You cut a very small grove all the way around the housing on the mating surface.
Note the evidence of oil leaking to the outside of the housing
Attachment 24461
First I cut a small grove using a ball file with a baby hobby tool
then I made the grooving tool to deepen the cut
Attachment 24462
This is a poor quality video since my friend nor I am are video graphics engineers
but is explains the process
https://www.youtube.com/watch?v=j-CXO0Ai5zc

I totally agree with your observations and comments on this issue, I do the same thing on my motorcycle engines on all mating faces and junk the gaskets.

http://www.homemadetools.net/forum/g...2000#post75558

Quote:

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Originally Posted by olderdan

I totally agree with your observations and comments on this issue, I do the same thing on my motorcycle engines on all mating faces and junk the gaskets.

http://www.homemadetools.net/forum/g...2000#post75558

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Yep, my dad told me that there has never been an automotive engineer who knew everything. I acquired a war surplus HD 45 sometime around 1968 he and I stripped it to the last bolt then rebuilt it our way. every mating surface had a tiny little grove cut in them either to hold the gaskets or to aid in sealing He had dozens of little tricks he showed me while we put it back together. Probably the only 45 in the country at the time that you could ride hard all day then park it on a white towel and not get shot by my mom for ruining her towel.
It doesn't take much of a grove on most things like motorcycle cases just a few thou wide and deep is enough. A lot of the Japanese cycles have groves made for "O" rings Imagine that!

Old-school people are just great

if cutting grooves in precison machined mating surface is not your thing ,, Its not mine.. just use permatex aviation form a gasket ,gasket sealer , or what ever its called these days, the dark brown black thick gooey stuff.to both sides of your gasket, nothing i have leaks oil !!!!!! and no i am NOT a fan of silicon sealer for engines and such , its made for weather stripping, and caulking use..

Quote:

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Originally Posted by madokie

if cutting grooves in precison machined mating surface is not your thing ,, Its not mine.. just use permatex aviation form a gasket ,gasket sealer , or what ever its called these days, the dark brown black thick gooey stuff.to both sides of your gasket, nothing i have leaks oil !!!!!! and no i am NOT a fan of silicon sealer for engines and such , its made for weather stripping, and caulking use..

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Hi
The Aviation sealer works but it is a PITA to take the unit apart afterwards and to clean before assembly. Try using Permatex Hylomar it seals just as well but is easy to disassemble and clean up for reassembly. Originally made by Rolls Royce to seal their engines. Use it on all my motors and no oil leak issues to deal with.

Hylomar sealant
I think the best thing about Hylomar is that it is non-hardening, defiantly my favourite. I'm not a fan of RTV because I have seen it gooped on and beads and strings of squeeze out, internally drop down and clog the oil pickup. That said I have used the right stuff sparingly on a lot on Japanese bikes and all sorts of cars because that is what is specified and never had a problem but I'm a nut on clean parts that are straight. I can certainly see the merit in the groove though.

One f the reasons why I grove the flywheel housings on heavy duty diesels boils down to this. Here you have an engine capable of close to or more than 2000 ft lb torque output or around 2800 Nm take your choice, and a transmission weighing over 800 lbs literally hanging on the back of this with a low reduction of 14 or 19 to 1 multiplying the torque from the engine to the driveline all of this is held together by 8 tiny little 15 mm bolts and 2 16 mm dowels.
When all you have is 2 flat machined surfaces mated together with a thin almost non existent thickness of sealant to keep oil from leaking all these forces are working against a long term proper seal even when no actual oil pressure is involved there is the fact that 2 dissimilar metals cast iron engine block and the aluminum flywheel housing react differently to stresses and most of all heat factor in a million miles or more of hard work that microscopic film of sealant is going to be eradicated so in a sense the only real seal you ever had was the squeezed out bead adhering to both parts. By adding a small grove to 1 of these parts I have created a cavity for the bead to be held between the parts instead of on the edges. I have effectively made an "O"ring out of the sealant. Will it ever leak? of course given the right conditions but so can "O" rings once they get old and brittle if there is ever any movement. But this engine has 925,000 miles on it and judging from the past 4 years of oil sampling I figure it to only have another 8 to 900,000 miles of life left in it or about 5 years I'm trying to talk my friend into buying an engine for me to rebuild and have sitting on the shelf so to speak just in case his engine dies. or I might wind up and install it in 1 of his other trucks.

Hello Frank,
I understand fully the reasoning and wholly agree with you. Basically you are mitigating a design fault. For the record I like like gaskets, real ones not goop but they are still subject to the same problem if the basic design is flawed.
Spare engine is a good idea. When I was working in the rubbish industry I and a couple of other guys convinced management to let us build a spare engine during occasional slack time. TWO DAYS after it was finished it was used and saved the company a lot of money in penalties,(we got a good stock of spares out if that). A rebuilt engine can also be sold if your mate decides to retire.

<!-- BEGIN /var/www/html/homemadetools/protected/modules/zeus/views/tool/postUpdate.php -->
Thanks Frank S! We've added your Groove Cutting Tool to our Transmission category,
as well as to your builder page: Frank S's Homemade Tools. Your receipt:

<div id="blocks"> <div class="block b1 pngfix"> <div class="bimg"> <div> <a href="http://www.homemadetools.net/homemade-groove-cutting-tool"> <img src="/uploads/215408/homemade-groove-cutting-tool.jpeg"/> </a> </div> </div> <div class="head pngfix"></div> <div class="left pngfix"></div> <div class="right pngfix"></div> <div class="blockover b1 pngfix"> <div class="title"> <a href="http://www.homemadetools.net/homemade-groove-cutting-tool">Groove Cutting Tool</a> <span> by <a href="http://www.homemadetools.net/builder/Frank+S">Frank S</a></span> </div> <div class="tags">tags: <a href='http://www.homemadetools.net/tag/seal'>seal</a>, <a href='http://www.homemadetools.net/tag/hand-tools'>hand tools</a>, <a href='http://www.homemadetools.net/tag/grooving'>grooving</a> </div> </div> </div> </div>
<!-- END /var/www/html/homemadetools/protected/modules/zeus/views/tool/postUpdate.php -->

The tool shown produced a rather rough groove. Now I have never worked on an engine part like this but I would imagine that a carefully sized dremel like cutter could produce a more consistent groove depth with smoother edges.

Quote:

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Originally Posted by Nick79

The tool shown produced a rather rough groove. Now I have never worked on an engine part like this but I would imagine that a carefully sized dremel like cutter could produce a more consistent groove depth with smoother edges.

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I made a tool on the lines you are suggesting here

https://www.homemadetools.net/forum/...2000#post75558

But what the hell Franks method works also.

I saw a groove like that on turbine generator set. The grove was cut by hand, and it had some grease nipples tapped into it at intervals. An RTV type material was pumped into the assembly( this was before silicone was big time) and there you had an o-ring type seal, simply elegant that it worked so well.

Not being high-tech in comparison, this method worked a treat for my washing machine tub DIY seal:
https://www.homemadetools.net/forum/...0-3#post159844

It's been operative and used every other day for over two months w/o any sign of leaking!
My (unproven) personal hypothesis for the groove is the rougher its inner surface, the better the bite gets for the sealant.
Thanks for all you guys pitching in, particularly Frank S & ToolMaker51 for leading me to this nice solution!

Cheers
Johan

Quote:

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Originally Posted by DIYSwede

Not being high-tech in comparison, this method worked a treat for my washing machine tub DIY seal:
https://www.homemadetools.net/forum/...0-3#post159844

It's been operative and used every other day for over two months w/o any sign of leaking!
My (unproven) personal hypothesis for the groove is the rougher its inner surface, the better the bite gets for the sealant.
Thanks for all you guys pitching in, particularly Frank S & ToolMaker51 for leading me to this nice solution!

Cheers
Johan

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I had been wondering how your washing machine was doing I knew you said it was working in your thread but the update is great news.

Great idea, Frank. I will remember this

Good idea. I have seen them use a silk thread between two mating parts in aircraft engines.

4 years and over half million miles later and it still doesn't leak. The truck now has over 1.4 million miles on it and the equivalent of 2.1 million on the engine due to having ran a truck mounted Vacuum/ pressure pump when the truck pulled a bulk tanker for years before Bob bought the truck. Still has 45 PSI oil pressure running 30 PSI idling, down to 415 HP from the 425 new uses 1 gallon oil in 7000 miles, the 3 oil filters and centrifuge filter changed every 25,000 miles, oil changed each 50,000.
Oil sampling still within tolerable levels but starting to see them gradually getting closer to unacceptable. Bob is thinking it is about time for me to reman the engine, both diffs. and replace the clutch for him.

I can see your point Frank for a groove to hold sealant. I have worked on & operated many different types of trucks in my career in the oilfield transportation business & I have NEVER seen a Flywheel housing that had to seal oil! The crankshaft oil seal is in the engine block not on the flywheel housing. There is also a starter bolted onto the flywheel housing which may be called a clutch housing also. In the bottom of that housing is an inspection plate through which you grease the throwout bearing & adjust the clutch "free play", also running through the flywheel housing is the clutch shaft with only bushings in the housing that need to be greased & are not sealed. I fail to see your reasoning to seal the mating surface of the flywheel housing to the engine block. IF you ever did happen to seal it all up & did develope an engine oil leak that would fill the housing and make your clutch, now running in oil, totally useless! You wouldn't get too many starts from that starter running in oil either as it is not a sealed unit.
Sorry Frank but I just cannot comprehend sealing a flywheel housing. Please contact me to show me how I am wrong in my thinking.

Quote:

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Originally Posted by Wildwilly

I can see your point Frank for a groove to hold sealant. I have worked on & operated many different types of trucks in my career in the oilfield transportation business & I have NEVER seen a Flywheel housing that had to seal oil! The crankshaft oil seal is in the engine block not on the flywheel housing. There is also a starter bolted onto the flywheel housing which may be called a clutch housing also. In the bottom of that housing is an inspection plate through which you grease the throwout bearing & adjust the clutch "free play", also running through the flywheel housing is the clutch shaft with only bushings in the housing that need to be greased & are not sealed. I fail to see your reasoning to seal the mating surface of the flywheel housing to the engine block. IF you ever did happen to seal it all up & did develope an engine oil leak that would fill the housing and make your clutch, now running in oil, totally useless! You wouldn't get too many starts from that starter running in oil either as it is not a sealed unit.
Sorry Frank but I just cannot comprehend sealing a flywheel housing. Please contact me to show me how I am wrong in my thinking.

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On the Mack E7 engine the crankshaft seal is in the flywheel housing the rear of the oil pan mates to a flat area just below the crankshaft seal . the crank seal is in many Cat engines, Detroit 71 series the 92 series and the series 60s all have the seal in the flywheel housing many Cummins are also done this way, About the only9 engines I remember off hand that had the seal in the block were the 855 series IE NT big cam 1,2,3,&4. Some Cat did not have the seal in the housing, And some Internationals I've worked on also had a dry housing between the block and housing
Some manufactures were even arrogant enough to use the flywheel housing to block off water ports in the rear of the block with O rings in addition to having the crankshaft seal in the housing
Attachment 44120
Attachment 44121

Quote:

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Originally Posted by madokie

if cutting grooves in precison machined mating surface is not your thing ,, Its not mine.. just use permatex aviation form a gasket ,gasket sealer , or what ever its called these days, the dark brown black thick gooey stuff.to both sides of your gasket, nothing i have leaks oil !!!!!! and no i am NOT a fan of silicon sealer for engines and such , its made for weather stripping, and caulking use..

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I used Permatex on the VW engine I rebuilt. That was the way it was usually done. Kind of gluing the crankcase halves together.