TC 102 exhaust tube

[red42hj]

Yes, its me again. Got a problem with my exhaust tube. on reassembly, with everything in the correct position I now find the exhaust tube appears to be too short. Never noticed this before. Even allowing for the water tube to bend out and away from the bottom there is as much as 15mm left uncovered of the bottom housing. with it all assembled the tube only fits over 5mm of the housing; leaving it quite loose. Checked the spares manual, and it is the correct 23.5 inches long.
Any ideas? Red.

[Charles uk]

Is the water pump housing in the correct position on the drive shaft tube?

[tambikeboy]

Just thinking out loud in the old scania mybe a silly question is the drive shaft all the way home at gearbox end.....

[headdownarseup]

Something else to consider, the top of the pumphousing where the exhaust tube sits over the top can become quite corroded over time. Does it look like it's been corroded away leading you to think it might be the wrong length/dimension. It can make the exhaust tube a bit wobbly at the bottom.
Double check everything is where it was originally when you took it apart in the beginning. Did you take any pics before you stripped it down!

Jon

[red42hj]

Yes the drive shaft is in the correct position top and at the bottom where it meets the pump housing. As a trial, I replaced the tube loosely without the internal water tube, and without the lower half of the gearbox, so there would be nothing to stop the tube from reaching full position except the outer drive shaft tube; and it still is too short!. that leaves me head scratching. now. Unfortunately I did not make notes or photos before taking apart. I have not run the engine for a few years, and had no problem before. ( but that's not to say it was right then). One query though; did these tubes normally have a slot cut into them for the water pipe outlet? Mine has not. I shall go into the garage today and look at it again. Watch this space!
Thanks to all, Red

[red42hj]

P.S. No ,there was no corrosion at the bottom housing, in fact there is a dirty mark where the tube sat, and it was only about 10mm over the end then. So maybe it was never right. ( and yet the tube is the correct length; weird.)

[tambikeboy]

If exhust tube is correct length and Yorkshire drive shaft is correct then what about drive shaft tube is it all the way home....

[Charles uk]

Is the exhaust tube brass or aluminium & ask Jon what is supposed to be on there.

[red42hj]

I've noticed there is a very shallow rebate on the bottom housing about half inch or so; over which the tube has been sat. but to my mind not only is it too short, the tube's diameter is too large for this and would sit further down if it were longer . I think maybe the tube is a bit of a rogue one. I think I'll try and find something more suitable and cut it to fit how I think it should be. Answer to your question though, yes the drive tube is in the right position above the pump, and the tube is chromed alloy. I'll get over this problem somehow. I'm not too worried about details; as long as it all works for the boat I'm happy. Thanks to all for your input. Red.

[headdownarseup]

Really quick and simple way to check to see if the torque tube is far enough into the pumphousing is to look into the cavity on the underside where the impeller would sit and you'll see the very end of the tube sitting in the housing. Very roughly it should (ideally) sit fairly flush to the bottom.If you see any saw marks on the end of the tube you know it's been cut down to match. Another way is to measure whereabouts the drain holes are in the torque tube. Pics will help me out here

Most 102's exhaust tubes for this age seem to be chrome on brass. Have a little look see on the inside of the tube and scratch the chrome away for a better look. Mid 60's onwards they seem to go for aluminium tubes. (bit noisier too)
The rebate you mention on the outside of the pumphousing is fairly normal. If you're lucky you might see around 10-15mm of coverage over the exhaust outlet which is pretty normal.The exhaust tubes don't normally have a slot cut into them to allow the water feed pipe a better fit! Can't think why yours would be any different unless it's been apart a long time ago and put back together wrong somehow.

Pics help a lot
Sometimes difficult to visualise what you mean.

Jon

[Keith.P]

My TC looks like this.

[red42hj]

Yes the torque tube does sit almost flush with the flange above the impeller. Also the photo from Keith seems to agree with what I have. The exhaust tube is rather loose at the bottom though which leads me to believe although everything is in the correct place, this tube may have been not an original item ,but one that was adapted for this purpose. If it does not rattle next season, it will be fine! Thanks, Red.

[headdownarseup]

Nothing too much to worry about with your exhaust tube so far, as the vast majority of seagulls have a "rattle fit" on the pumphousing anyway.
If it annoys you that much (and it would with me too) see if you can make the pumphousing a tighter snug fit by painting the "rebate" with some zinc primer or similar, or better still some insulation tape.Try not to cover over the slot for the water feed pipe. 2 or 3 wraps of tape might just do it.

Failing that some epoxy putty on the "rebate" to tighten up the fit.
Whichever works for you, as long as you won't see it when it's all buttoned up.


Jon

[Collector Inspector]

I like the term "Rattle Fit".



BnC

[red42hj]

yes I agree (headownarseup) I was thinking along those lines myself. Thanks to all for your help; until my next problem,
Cheers for now, Red.