Oil feed banjo to cams measured 0.630 inch thick. Replaced original copper washer with thicker washers after annealing them to cherry red and allowing to air cool. Measured together both old washers are 0.065 inches thick and both new washers measured 0.111 inches thick. With caliper measured from base of banjo bolt head with one new washer installed to center of cross feed hole in bolt. It is exactly in the center.
Looked in the manuals but did not find torque for the banjo bolt. If you know for sure what this value is please advise.
Oil feed banjo to cams measured 0.630 inch thick.
Measured together both old washers are
0.065 inches thick and both new washers measured 0.111 inches thick.
With caliper measured from base of banjo bolt head with one new
washer installed to center of cross feed hole in bolt. It is exactly
in the center.
So the distance from the underside of the banjo bolt head to the center of
the cross feed hole is (0.630 / 2) + (0.111 / 2) = 0.370?
Maybe Jaguar actually fixed that design error somewhere along the line.
That’d be nice. But if so, why would they still be using the thinner copper
washers?
Looked in the manuals but did not find torque for the
banjo bolt. If you know for sure what this value is please advise.
If you’ve assembled the OEM banjo bolt with the thicker aftermarket
washers, you have very little thread engagement with the soft aluminum
tappet block. Be VERY careful not to overtighten! Just enough to get those
softened copper washers to seal, then stop.
Some prefer to replace the OEM banjo bolt with a longer version to get more
thread engagement. There doesn’t seem to be a problem with using a
longer banjo; the threads into the tappet block are threaded deep enough,
and it doesn’t block off any oil passages or anything. We had a guy here at
one time that was offering homemade banjos a bit longer. Unfortunately, I
suspect a lot of people were going that way AFTER they had stripped the
threads out with the shorter OEM banjos!
– Kirbert
Using the thicker copper washers as described there is only 0.0235" of thread engagement lost. Snugged it down as you say to just crush the softened copper. Will let all know if it leaks when I get the engine back in next week with the rebuilt TH400 and new torque converter. Waiting on some electrical connectors and terminal boots which need replacement .
Using the thicker copper washers as described there is only 0.0235" of
thread engagement lost.
I dunno about your math. You just told us the thicker washers added up to
0.111" while the originals added to 0.065". 0.111" - 0.065" = 0.046" of thread
engagement lost. That normally wouldn’t be significant except there’s scant
thread engagement to begin with!
The general rule of thumb in designing threaded attachments is that the
thread engagement should equal the diameter. When a soft material such
as aluminum is involved, the thread engagement should be 1.5x the
diameter. With that banjo bolt, I don’t think there’s 1x the diameter
engagement to begin with, and it’s into aluminum. Arguably a special case
as the threaded attachment isn’t providing a structural attachment but rather
a simple oil line connection, but it’s still somewhat odd that Jaguar didn’t
make those banjo bolts a bit longer just to avoid issues with stripping.
– Kirbert
I have the longer banjo bolts and the thicker washers Ron used to supply. Torqued them to the factory specs, Yes, they are AVAILABLE. Units are Nm
Best regards,
Steve
Thanks for your message. Where are the longer oil feed bolts available? Also interested in source for improved gasket for the sandwich plate and oil pan.
NLA. Ron Kelnhofer used to make them, but he quit.
Updated gasket from the dealer.
Steve
Ron Kelnhofer used to make them, but he quit.
Does anyone know what thread those things are? If it happens to
correspond to some available bolt size, it shouldn’t be too difficult to make
your own. Yeah, you’ve gotta drill the bolt lengthwise, but that’s easier than
you think – especially if the bolt you start with isn’t too hard. Drilling the
cross hole – in the correct location – is a snap.
When buying bolts, I’d buy whatever length bolt has the correct length shank
under the head, regardless of overall length. I think the shank needs to be
about 3/8", maybe 1/2", somebody measure one and report. Then saw the
end off to end up with a bolt that’s perhaps 1/4" longer than the OEM banjo.
Drill lengthwise, drill cross hole, done. You MIGHT want to grind half the
head off to reduce the height just to make it a bit easier to get in and out
when the engine is fairly close to the firewall.
– Kirbert
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Wrote down all the dimensions of the oil feed bolt, and just spent 20 minutes looking for that piece of paper with no luck. Forgetting more and more lately. Now what where ewe discussing. Oh yeah. I do remember that the shoulder of the bolt was exactly 0.500 and had polish finish which extended only so far so as not to interfere with the threads in the block. The cross hole had slight reliving grinding which is suppose was to prevent cracking.
If I find the notes later will send a message to you Kirby. It had all the measurements except for the thread size. The thread s where very course of course☺.
Wrote down all the dimensions of the oil feed bolt, and just spent
20 minutes looking for that piece of paper with no luck.
You’ve got a bad case of CRS.
I do
remember that the shoulder of the bolt was exactly 0.500 and had
polish finish which extended only so far so as not to interfere with
the threads in the block.
Yeah, you don’t want it too long. Too short would work, but having both the
threads and the cross hole in the same area might make it too weak. It’s
better to have a shank there.
The polish finish is irrelevant. Could be a crummy finish, it’s not a seal or
anything.
The cross hole had slight reliving grinding
which is suppose was to prevent cracking.
Also not strictly necessary, but actually might help improve oil flow a bit.
Easy to do with a Dremel or perhaps even by hand with a countersink bit.
It had all the measurements except
for the thread size. The thread s where very course of course.
I recall them as very coarse indeed, which worries me a bit for finding a
generic bolt of the same thread.
– Kirbert