Topic: Is this fixable?

[Rookster]

I bought a set of engine cases for my long term project and found this.  Anyone have any thoughts whether this is able to be welded?





Scott

[calj737]

Yes, BUT… the cases need to be deep cleaned numerous times. The “repair” will involve grinding back some of that area then building up a new “pocket”. Probably need to finish it with 2 end mills to get the interior diameters back to correct size. The exterior is probably unimportant from an appearance perspective.

Welding 40+ year old oil/grease-soaked aluminum will not be fun and will torment your welder. Expect to be charged accordingly. I’d estimate (if the parts were properly cleaned by you) 4 hours of work between welding and machining. Your quotes may differ…

[ekpent]

What year/model of upper case is that ?

[RAFster122s]

Wouldn't it be cheaper to get another new set of cases in better shape than spend quite a bit on a repair???

[Rookster]

It's a set of K1 cases from January 1971.  There were a few surprises but this was the worst.  I bought them online and was told they were in usable shape.  The pictures looked decent but I should have known better.  They are matching halves and share the same number on the back.
 There were a few broken off screws stuck in them but I got those out along with the roll pin for the Kick start shaft.  Next up was to remove the cylinder studs when I came across this. Good earlier cases are hard to find so I took a chance.
Scott

[Rookster]

Wouldn't it be cheaper to get another new set of cases in better shape than spend quite a bit on a repair???

Yes but these cases are only a few hundred numbers away from my K1 which has a K4 engine in it currently.  I am willing to spend the money to build this into an engine and eventually it will make it into the K1. 

Scott

[Ujeni]

You are looking at $500 at least if it were done where I live. A late K1 is right on the edge of common and valuable. If it was a sandcast or a K0 diecast, I would say go for it. With a late K1 I don't know if the value will justify the money you are going to spend fixing the upper case. If it is special to you, then, by all means, have it repaired!

BTW, is there more damage in that area on the lower case? Hopefully not. I suspect the damage occurred when someone was trying to remove a stuck spindle. Hopefully not evidence of a more catastrophic incident!

[grcamna2]

I realize tig? welding will require lot's of cleaning and prep work;do you have another old top case which you can remove part of that one piece that's been broken off ?  You may be able to do plenty of the prep work yourself by measuring what the length of that part should be,cutting a good one off a donor case,then match/dress both parts and get them ready to be welded together by a qualified welder who will both clean/prep(put the case in a special industrial oven to heat it for many cycles until all/98% of the oil has seeped out of all the pores of the cast aluminum top case,then wash it again & again)and weld the donor piece on there and make sure it's as the original length. I think it's good that almost 1/2 of the broken original,machined factory casting is still intact.
The expert welder can then weld the donor part you gave him to the areas you've already carefully measured & prepared;use the steel starter gear shaft to hold the prepared donor part in place along with what's left of the original part that's still intact until it's all squared-up and ready to be welded on there.

I had a set of dirt bike cases repaired before which had cracked on the bottom in 2 places on only one side of a vertically split crankcase set;a problem for the welder to be sure not to weld on the machined side where both cases fit together..         I gave the job to a welding teacher at a 'Tech' high school in Indiana,Pa. who explained the process to me. 

[WideAWAKE]

Try contacting saints engine and machine.

He does A LOT of repairs of this nature.

[scottly]

For the welding, you might try contacting member Jim F.
http://forums.sohc4.net/index.php?action=profile;u=4044
You will still have to deal with machining the new hole, and in the proper location, which may be more difficult than the welding.

[newday777]

Wouldn't it be cheaper to get another new set of cases in better shape than spend quite a bit on a repair???

Yes but these cases are only a few hundred numbers away from my K1 which has a K4 engine in it currently.  I am willing to spend the money to build this into an engine and eventually it will make it into the K1. 

Scott

Where are you located Scott?(not in your profile)

[Rookster]

Thanks for all the responses.  I am located close to Buffalo, NY.  I might be on the lookout for another set of cases with a close number.  The first order of business will be to clean these cases and then see if anyone local can do it for reasonable money.  I do have a few sets of broken cases that I could use to cut a donor piece off.  I'm not sure if the welder would want that or if he would just build it up with new material. 

Scott

[RAFster122s]

Find someone who has done the job plenty of times or you might not like their results...
They are going to have to have an oven to do the work properly and lots won't have that and would depend upon you to have cleaned it well enough. Trying to depend upon the heat of the weld to drive pit impurities of oil is a recipe for bad results. Having seen several examples on the forum of various repairs it is clear the skills of various repairs varied greatly.

[calj737]

You don’t need an oven. The best prep would be to have the cases vapor blasted inside and out. That’s a double benefit- 1. You get them really clean. 2. The resulting exterior finish is awesome.

And you don’t want to “graft” a piece onto that case. It wants to be built up. A donor piece will be extremely weak when welded due to the nature of welding cast aluminum.

Biggest trick is to find someone who can weld it and machine it. Or you’ll need two contractors.

[grcamna2]

I spoke with a friend who understands welding cast aluminum and he recommended getting a piece of round copper and turning it down in a lathe to the same diameter as the steel starter gear shaft;he then recommended to have someone hold(pliers)the piece of copper in the hole and tig weld around the copper shaft until it's all built-up the way you want it.
He then told me the copper will be able to be slid/turned out and removed from the hole? after the repair;the tig will not stick to the copper.
The cast aluminum needs to be completely cleaned and prepped first.

[wolf550]

hey rookster what engine numbers were the k1 in January of 71 or what is your frame number?

[MRieck]

Yes, BUT… the cases need to be deep cleaned numerous times. The “repair” will involve grinding back some of that area then building up a new “pocket”. Probably need to finish it with 2 end mills to get the interior diameters back to correct size. The exterior is probably unimportant from an appearance perspective.

Welding 40+ year old oil/grease-soaked aluminum will not be fun and will torment your welder. Expect to be charged accordingly. I’d estimate (if the parts were properly cleaned by you) 4 hours of work between welding and machining. Your quotes may differ…

That and hitting pockets of zinc.

[Rookster]

The frame is 1076xxx.  I was looking for something within a few hundred numbers of my frame. 

Does vapor blasting damage the gasket and bearing surfaces?  I would think those need to be taped off with something that won't get blasted away.  Does anyone have a contact for vapor blasting in the NorthEast? 

Thanks
Scott

[Geoff Hastings]

Lots of conflicting opinions but here’s mine, wash it off, take it to a proper mig welder. Collect the welded case and then drill and tap the repair. Job done. I had this cracked case welded and it don’t get much dirty and oilier than that. I did have to clean up the mating surface with a file but there’s no leaks or problems.

[scottly]

The best prep would be to have the cases vapor blasted inside and out.

Vapor blasting won't do anything to remove any oil trapped in the pores of the metal, it only affects the outer surface.
My buddy Henry did quite a bit of welding on motorcycle parts, and his advice was as soon as contamination appeared in the weld puddle, stop welding, let it cool off, then grind out all of the crap with a burr. Repeat as needed.
BTW, Jim F has quite a bit of experience welding; he's the guy that welds broken carb float posts.

[wolf550]

The frame is 1076xxx.  I was looking for something within a few hundred numbers of my frame. 

Does vapor blasting damage the gasket and bearing surfaces?  I would think those need to be taped off with something that won't get blasted away.  Does anyone have a contact for vapor blasting in the NorthEast? 

Thanks
Scott

gotcha
I can check with the guy I got my engine from if he has another 750 motor around 1076xx hiding in storage
I got a 1055637 motor from him recently

[calj737]

The best prep would be to have the cases vapor blasted inside and out.

Vapor blasting won't do anything to remove any oil trapped in the pores of the metal, it only affects the outer surface.
My buddy Henry did quite a bit of welding on motorcycle parts, and his advice was as soon as contamination appeared in the weld puddle, stop welding, let it cool off, then grind out all of the crap with a burr. Repeat as needed.
BTW, Jim F has quite a bit of experience welding; he's the guy that welds broken carb float posts.

I have welded tons of cast aluminum. And I can tell you with absolute certainty that vapor blasting will create a weldable surface. It’s also true that as you weld and apply heat from the torch, trapped contaminants will surface. But an experienced welder will run the torch without filler over the base surface to boil out any “goo”. This then gets peened, then a filler pass. Peen, filler pass, peen, filler pass, etc until the build-up is complete.

No, vapor blasting will not harm mating surfaces, but sand blasting can. And anyone who vapor blasts will first heavily degrease the cases so they are as clean as possible beforehand. The benefit of vapor blasting is the process does gently peen the surface so further surface contamination is reduced.

And yes, Jim F is an outstanding micro welder. I have no clue whether he does case repairs like this. TIG is the correct process here not MIG.

[Tracksnblades1]

If it were mine, after a thorough cleaning (You know acetone, aluminum burrs, oven time, reclean etc),

First, I’d use a later model TIG welder with a gas lense, set your AC balance to where the torch provides the best cleaning action. Try it on your repair area to see where the best cleaning action occurs. Do not puddle yet just find the best cleaning action for your cast aluminum piece. I’d try somewhere between 30 and 40% positive and 60 and 70% negative and leave it where you observe the best cleaning action with no puddle forming.

Second I’d mount your piece on a bridge port and locate your hole. Protect the table and controls from the high frequency.

Third after preheating, I’d weld the hole solid with 4047. It melts at a lower temp so you don’t have to melt as much impurities out of the casting.

While it’s set up on the mill. Drill it and tap it..

All while following Scott’s and 737 techniques and advice. I personally don’t know how the soda blasting affects the weld.
I’ve done the bead blasting before. Usually with good AC cleaning action it’ll remove the imbedded glass and allows a decent weld. Never tried sand blasting aluminum. While welding it, if you have an impurity that won’t allow the puddle to advance or close, I’ll usually stop and remove it with a drill or burr instead of trying to cook it out.. I’d keep my heat just adequate to puddle and melt the rod while advancing. High heat will bring more casting impurities to the weld zone…keeping your filler Rod’s hot tip under the gas lense’s shield will keep you from contributing any contaminates too.

An experienced TIG welder will make it look easy….😇

[Rookster]

I took the case to a local weld shop called Weld All.  They told me they could weld it and hand it to their machine shop guy to remake the hole.  They wanted the reduction gear shaft for measurement.  He told me not to clean the case as they would do what needed to be done and some chemicals react to the weld process.  I dropped it off on Friday and picked it up this morning.  The shaft is a nice slip fit.  I am pleased with The work.  I won't really know how exact the hole is until it's ready to be put back together.  At this point I am going to go forward with these engine cases and hopefully within a year have a running engine.





Thanks for all the advice.  It helped me understand the welding process better.
Scott

[grcamna2]

This repair looks very good