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Thread Like Summary
Excalibur, slofut, tridentt150v
Total Likes: 4
Original Post (Thread Starter)
by Randy Richardson
Randy Richardson
I'm thinking about tearing down my 68 Bonneville engine this winter to replace the sludge trap.
But here's the deal- The bike runs great, has 150 psi in both cylinders and you know the old "if it ain't broke don't fix it" thing.
I've put 10,000 miles on her but have no idea how many miles were on her when I bought her 4 years ago.
She's a rider- not a hider.

So I'd like your votes on what you think is the best choice with the lowest risk.
1. Leave it alone and rebuild the engine when and if it spins a bearing or whatever?
2. Replace the trap myself? I'm a shade tree mechanic. Have watched Hughie's DVD, Lowbrow's and many other YouTube instructions.
I do my own maintenance (clutch, timing chain, harness, voltage reg, EI. etc etc but have never rebuilt an engine.
3. Have the engine rebuilt by a "professional"? Is it better to dance with the "devil I know" (me) or the one I don't (the pro)
I don't know what shops are good or bad. But I don't know those gotchas that are learned by experience either.
Any good shop recommendation would be appreciated.
So what-da-ya think?
1,2, or 3?
Liked Replies
by quinten
Originally Posted by slofut
Oil pressure was what I was getting at. I'd put a filter and an oil pressure gauge on it and ride it! Don't take it apart!

There is a conundrum here .

A full sludge trap may boost oil pressure ... the measurement is before any oil is used .
it tells you the pump is working and the seals ... up into the crank are too .

you would have to fit a gauge
after the sludge trap , rods and drive side bearing ... to know how far useful oil pressure or volume is getting .
2 members like this
by kommando
Option 1 was the factories expectation, ie the sludge trap was to be cleaned out when the engine was being overhauled after wearing out. Fit an oil filter in the return line to reduce the particles that cause the sludge is good insurance and helps the engine last longer.

An oil pressure gauge would show an increase in oil pressure close to the point the trap became blocked and the drive side rod lost its oil supply.
1 member likes this
by John Healy
John Healy
The Triumph twin has had a center feed crankshaft with a bronze bush or rubber seal. The early, pre-oil seal, version using a bronze bushing gave very little trouble.

When I see (or heard of (over the years we have serviced over 600 dealers)) problems of rod bearing failure, it is usually a bike that was last run on non-detergent oil, and at some time in its life put into storage for a while (barn find). When brought back to life the old non-detergent oil was drained and modern (detergent) oil filled the tank. I have seen, and had the likes of Jack Wilson of Big D Cycle, report, that he just had a bike seize on the stand during the first start-up after being in a long "sleep."

While certainly it is rare for a rod bearing to seize from a blocked sludge tube. But, with parts getting more-and-more expensive, and in some cases hard to find, A little bit of insurance before fitting an oil filter is not out of the question.
1 member likes this
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