'71 Roosa Master DBG cam pin split

[RuralTowner]

Unfortunately the only dedicated machine shop that I knew to exist in my area...the old man retired a years ago now. Must've already been in his 70s at the time. Last time I saw him was about 6 years ago to take a warped 22R head to be planed.

Have 1 last thing to try. Have a 12 pt 3/8 deep socket that fits down in gets partial engagement on the remnants if encouraged. Go through the back & try to weld it into place. Either that or use a turned down pc of old steering shaft w/ the tip slightly counter sunk to cup what's left of the ball better than the socket. Chunk can go back in place so it's more even & will give unhindered access inside like the socket which has a restriction just after the drover socket. If the rest of the pin snaps it's definitely getting milled out. Found a local race shop where the owner seemed confident he could get it out when I brought it by but will drop Disel a message.

 

[m16ty]

Looks like it's time for the die grinder or Dremel and a good cutting bit. Or have a machine shop mill the head off. Worst case you would need a new cam ring. IMO. YMMV.

That is something I haven’t thought of, and it might work if you can find a way to stabilize the cam ring steady enough. The main thing that would worry me about that is all the shavings and chips you are going to get into the pump.
I’ve got an old Roosa Master repair manual and the procedure listed for this situation is to cut the housing to get the pump apart. The reasoning is, housings can be gotten a lot cheaper than most internal parts. Still going to get some debris in the pump doing this, but it will be aluminum and not as harsh as steel.

 

[RuralTowner]

Weld attempt only eventually succeeded in shearing 90% of what was left of the head. Leaving the shank & lower part of a ball edge. Bright side is it leaves more working room. Time to find the Dremel or invest in one & lots of little grinder heads. Also now to check msgs.

 

[Dieseltech]

Time to sacrifice the housing and HOPEFULLY save the cam ring if it's still good...

 

[RuralTowner]

Time to sacrifice the housing and HOPEFULLY save the cam ring if it's still good...

Any of the DB housings should be compatible? Besides fact of needing to find or make covers for triangular timing windows if a housing is missing it.

Most I'm finding are DB2s. Some complete DBGs turn up cheap with same style body parts I'm after but don't have the patience for another potential pin to fight even though I now have the tools to nigh guarantee the pins stay together. The top cover I know is the primary difference.

 

[Dieseltech]

The DB 2 is the latest housing, and MOST have the angled injection line outlets your early pump does not have. NOT ALL DB housings are the same either, and you need the CORRECT brass pilot tube for the drive shaft also.

 

[RuralTowner]

The DB 2 is the latest housing, and MOST have the angled injection line outlets your early pump does not have. NOT ALL DB housings are the same either, and you need the CORRECT brass pilot tube for the drive shaft also.

So check that the housing has the brass bushing. Will request end-on confirmation where needed. Since the shaft stayed behind on the loader they used brass?

All salvageable internals plus the head would be swapped over. Found a good serviceable 4 lobe cam IF necessary.

Any whole pumps was already looking at the radial side mount ports.

 

[Dieseltech]

The brass bushings for service are epoxied in place, almost all the pumps I repair need that new bushing. There are LOTS of four lobe four cylinder cam rings too, they are NOT all interchangeable.

 

[RuralTowner]

Understood on the cam ring. Lift & timing differences etc. So sure they'll fit but won't work or correctly. Won't know this pump's for certain until removed.

As destroying the housing is the point of no return how millable you think the very hard metal pin is in such a confined space?

Alternately if a suitable db2 housing is found must it already have the brass bushing or can it be altered to take it? This it be sent it out for.

 

[Dieseltech]

I doubt that hardened pin can be milled WITHOUT destroying the housing...

 

[RuralTowner]

Using a dremel then looks like only option to preserve the housing.

Equipment dealer I checked with also would've likely tried a weld method among who knows what else but turned it down for liability reasons. Understandable if anything were to happen on their part they'd be owing a pump. The race shop's owner claimed he "hadn't found anything he couldn't remove yet" which I'd be having that in writing IF the offer was taken.

Alternate housings if one can be found MUST they already have the brass bushing or can they be made to work with? Especially if the snout of the destroyed housing was provided as reference?

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These pumps being simple to disassemble for cleaning//re-seal is one thing. But the moment that pin split it's fate was effectively sealed it as an exchangeable core. It'd be lucky to earn partial credit with it's guts.

 

[Dieseltech]

There are three brass tube lengths and two lengths of steel tubes used in most DB pumps on Ag engines. I've swapped out housing tubes as needed and epoxied in the correct tube the spec sheet called for several times in my years of pump repair.

 

[RuralTowner]

There are three brass tube lengths and two lengths of steel tubes used in most DB pumps on Ag engines. I've swapped out housing tubes as needed and epoxied in the correct tube the spec sheet called for several times in my years of pump repair.

Sending DM*

EDIT*: As soon as I can get some finds I thought I had sorted...straight.

 

[m16ty]

A carbide cutter in a mill should handle the pin no problem. The problem is I don’t know how you would hold the cam ring from moving, once the cam ring moves while you are trying to mill you’ll break cutters and other nasty stuff.
I’m just a novice pump man, but I have several pumps just for parts. If an engine throws a rod or some other failure, most of the time people will just throw the whole engine away, never thinking to rob parts like the IP. All of my spare pumps I’ve got for free.

 

[RuralTowner]

The topside of the cam ring has a hole opposite the pin it looks like. Some kind of retainer that fits in the upper housing that's snug between the walls & has a peg sized to properly fit in the hole could hold it still. Then it becomes a matter of making sure everything is properly centered.