Sludge trap cleaning tips

[veltro_nero]

I tried searching but couldn't find a thread with the info I needed...

Just finished completely stripping down my V700 engine for the purpose of cylinder Nikasil plating and sludge trap cleaning. I attempted to remove the sludge trap plug using a 10mm allen key with a bar attached to it for leverage and I can't get it to budge. Instinct is telling me to get a 10mm hex impact driver and remove it using the impact gun, but I'm worried that'll just destroy the hex in the plug since it's soft aluminum. Any tips on getting it out? Guzziology says to destroy it, but I'm not sure how I'd get it out (chisel?) and I don't want to ruin the crank threads any worse than they are with the plug being punch in two places.

[geodoc]

I tried searching but couldn't find a thread with the info I needed...

Just finished completely stripping down my V700 engine for the purpose of cylinder Nikasil plating and sludge trap cleaning. I attempted to remove the sludge trap plug using a 10mm allen key with a bar attached to it for leverage and I can't get it to budge. Instinct is telling me to get a 10mm hex impact driver and remove it using the impact gun, but I'm worried that'll just destroy the hex in the plug since it's soft aluminum. Any tips on getting it out? Guzziology says to destroy it, but I'm not sure how I'd get it out (chisel?) and I don't want to ruin the crank threads any worse than they are with the plug being punch in two places.

My SOP for that is to drill the plug out to a diameter that just leaves the plug threads + a little using drill press, then with a pick, pry out the plug remains. Chase threads with a tap purchased a considerable expense from a local machine tool outfit. Clean out the sludge and install new plug with red locktite.

Out of curiosity, chrome bores on the V700 that's removed and Nikasil applied to clearance spec for same pistons? Getting it done at Millenium?

GD

[John A]

I use a tap with the same thread pitch and use it as a scraper so size is not important,just keep scraping until the threads are purty good. I assume you have a new plug. The factory dings the threads after they install the plug. I would use an impact before I drilled it out, they usually come out.

[veltro_nero]

That's the plan (Millenium that is). The cylinders and pistons were put in brand new in 1974, and the bike last ran in 1976 and then was parked for the next 40 years. The chrome bores actually look great, just don't want to put a time bomb in an otherwise mostly rebuilt engine.

I think I'll try impact gun as John said, if that doesn't work I'll likely just take it to a machine shop (yes I already have a new plug to put in). I don't have a drill press, so if they can just drill it out pretty well, I do have the tap to clean everything out.

[Don G]

Drill the punch marks with an 1/8" bit or so until the punch mark is gone, then try to remove the plug.  DonG

[Chuck in Indiana]

From memory when I was working on the Monte Carlo Guzzi.. a die grinder to clean up the punch marks and rattle gunned that sucker out of there. It must have been easy because I don't remember a struggle. I *do* remember drilling out the accumulated chrome and stuff out of the sludge trap. It was packed absolutely full. (!) The DPO had run a heater hose from the breather back behind the license plate to put the blue smoke behind him.. 

[veltro_nero]

Attempted to remove it using above methods, succeeded in destroying the female hex. Will be drilling it out tomorrow, I think this thing sitting for 40 years helped everything seize nicely, it certainly did with the oil drain plug on the sump!

[Bonafide Bob]

I tried searching but couldn't find a thread with the info I needed...

Just finished completely stripping down my V700 engine for the purpose of cylinder Nikasil plating and sludge trap cleaning. I attempted to remove the sludge trap plug using a 10mm allen key with a bar attached to it for leverage and I can't get it to budge. Instinct is telling me to get a 10mm hex impact driver and remove it using the impact gun, but I'm worried that'll just destroy the hex in the plug since it's soft aluminum. Any tips on getting it out? Guzziology says to destroy it, but I'm not sure how I'd get it out (chisel?) and I don't want to ruin the crank threads any worse than they are with the plug being punch in two places.

I have good luck getting smaller size bolts loose using a hand held impact that you tap with a hammer.

[canuck750]

Twice I have used an impact to remove the plug, once the damn plug was so seized that I needed to drill it out and tap the remaining debris to remove all remnant of threads.

The crank is made of damn tough steel, the plug will deform before you can begin to damage the crank.

Some heat around the plug will help.

[Antietam Classic Cycle]

It seems the earlier the engine, the tougher the sludge trap plug is to remove. On early engines they deform/peen the crank threads, later engines they just peen/punch the plug itself. 

[Bob Wegman]

On Triumph motorcycles I used to drill a couple of of threads where the plug was peened a small drill bit about 1/8 inch.

[Vasco DG]

With ones I couldn't move I drilled a row of small holes across the plu then hit each side with a punch. They collapse inward and can then be plucked out. Chase the threads with a tap.

Pete

[Tobit]

Regarding sludge traps, are they present on automotive crankshafts?  The only discussions I see about the traps are related to plain bearing motorcycle cranks.

Going to look at my 1920s era Audel's automotive texts tonight.

Tobit

[veltro_nero]

Well, I just wound up taking it to an old machinist who did some work on my Aermacchi years ago. He wound up drilling and chiseling as suggested. Really not too bad in there, obviously I'm going to clean it thoroughly, but maybe this bike really does only have 19k on it. More pics in the blog in the signature.

[dxhall]

From the been there, done that crew:  pay the money and buy the tap.