haggis Posted February 19, 2020 Report Share Posted February 19, 2020 Hi all, ☹️After 5 years of progressively worsening oil consumption, it was confirmed today that my car needs a bottom end rebuild. There was someone a few months ago who had a set of +40 pistons for sale on the classifieds, anyone got a set out there? thanks Hag Link to comment Share on other sites More sharing options...
johny Posted February 19, 2020 Report Share Posted February 19, 2020 I think you mean top end rebuild dont you? Can I ask what compression readings youve measured? Link to comment Share on other sites More sharing options...
haggis Posted February 20, 2020 Author Report Share Posted February 20, 2020 Hi Johny, I took it to a garage to do the test, and they said 135 dry, 235 wet, which I have read as being in the bore rather than the head. hag Link to comment Share on other sites More sharing options...
johny Posted February 20, 2020 Report Share Posted February 20, 2020 yes that does show pressure was lost past the rings rather than the valves but I dont think the dry reading is too bad its more that the wet reading is very high. Were the readings all pretty much the same as that is unusual with a worn engine (think 1 and 6 tend to wear fastest)? When does it smoke exactly, acceleration etc and how many miles do you think the engine has done? Link to comment Share on other sites More sharing options...
Clive Posted February 20, 2020 Report Share Posted February 20, 2020 The head needs to come off and inspect the bores. It is entirely possible that it may just need a hone and a set of rings. If it needs new pistons, I believe std herald 1200 pistons can be used, but need a big over-bore. But means the engine can be fixed.... and will go a bit better! Link to comment Share on other sites More sharing options...
Pete Lewis Posted February 20, 2020 Report Share Posted February 20, 2020 the wild variance from a reasonable dry at 135 to silly wet at 235 would make me disregard the findings and have it tested by someone who knows what they are doing buy a simple gauge from any factors or site and do your own good battery . best hot, all plugs out and throttles open on the 1600 do check the breather by the fuel pump has clear gauzes under its pipe flange are you sure its burning oil , when does it smoke ??? Pete Link to comment Share on other sites More sharing options...
haggis Posted February 20, 2020 Author Report Share Posted February 20, 2020 Hi guys, we’ll it’s been consuming Oil for some time now, around 1/4 of the dipstick every 50/60 miles. I tested it myself and posted the results on here last year and the readings showed minimum between dry & wet. As the head was converted and rebuilt some 28 years ago and I’ve only done about 10k in that time I doubted my results and have got a second opinion. He’s an old school mechanic and looks after a lot of classics for people in my area. You are correct in thinking it might just need new rings and honing, but if it needs a rebore and pistons it could be off the road a hell of a long time trying to find a set. Best case here I have a spare set of pistons for the future. breathers have been cleaned out and checked. I like the idea of the 1200 pistons especially if it improves performance, is it just the case of reboring to the new size? With all other parts the same. I think Pete mentioned this in my post last year. And what CC would it make it, any ideas? thanks hag Link to comment Share on other sites More sharing options...
NonMember Posted February 20, 2020 Report Share Posted February 20, 2020 The 1200 pistons are quite a significant oversize - you end up with 1147*1.5 = 1720cc I've read that there may be marginal clearance to some water ways, though, at such an overbore. 1 Link to comment Share on other sites More sharing options...
Pete Lewis Posted February 20, 2020 Report Share Posted February 20, 2020 1200 13/60 1600 all have the same stroke 1200 bore 69.3mm 1600 66.75mm gives you around 1720 cc on 6 pots my 1600 was at +060" and (bit smaller than 1200 ) but never a problem the head gasket on the 1600 is a steel shim, and tends not to blow out but if head washers have deformed you may just have cam box oil getting consumed due to lost clamp/torque on the studs believe you did calibrate the dip stick on your last exercise ? dont want it overfilled pete Link to comment Share on other sites More sharing options...
Nigel Clark Posted February 20, 2020 Report Share Posted February 20, 2020 The very high wet compression test result suggests the mechanic put too much oil in the cylinders, artificially raising the compression ratio. As has been said, get someone who knows what they're doing to repeat the test. The cylinder head will need to be removed anyway, when you will be able to examine the bores for wear. Is the exhaust smokey, and if so, under what conditions? Smoke when accelerating suggests worn piston rings and/or bores. Smoke on starting and on the overun is usually worn valve guides (there are no valve stem oil seals). Nigel Link to comment Share on other sites More sharing options...
johny Posted February 20, 2020 Report Share Posted February 20, 2020 If the bores were acceptable 28 years ago and youve only done 10k I cant see it needing a rebore. Its more likely a deglaze and/or new rings will be sufficient. I suppose we've asked before whether its had the dastardly external oil feed modification done? Link to comment Share on other sites More sharing options...
haggis Posted February 20, 2020 Author Report Share Posted February 20, 2020 Hi guys, no external oil feed. 28 years ago a ‘bore’ was someone I didn’t want to sit in the pub with. I’m a little wiser now, I do remember the pistons moving around in the bore though. Definitely smokey on start up, and a friend followed me and said she was smokey as I drove. I measured qty of oil when I changed it last year and the dipstick was spot on. I’ll take the head off, just need to place to leave it and work on it, a single garage ain’t quite big enough. Thanks. hag Link to comment Share on other sites More sharing options...
Colin Lindsay Posted February 20, 2020 Report Share Posted February 20, 2020 Take the head off and have a look at the piston bores - I've just done this on a 1200 engine so am an expert! (Before, if an engine didn't show any visible signs I just replaced seals, timing chain and core plugs and got another 10000 miles out of it...) I can feel a slight ridge with fingertips or fingernails at the top of the piston bore - see photo - which doesn't feel like much but then when you think of it, boring out 1/10,000 of an inch isn't much either. A couple of good mates told me it only required a deglaze with a hone; a second told me it was beyond help (using a solid earthy four-letter expression, which rhymed with ducked) and a block-machining expert states it's not bad and we'll get away with +20 pistons at most. It's his opinion I'm taking as gospel! It's at his business at present and I'm waiting on an update. The external symptom was a plume of blue smoke from the exhaust when any power was applied. Link to comment Share on other sites More sharing options...
johny Posted February 20, 2020 Report Share Posted February 20, 2020 of course bores can go oval as well and in different places so I suppose even without much of a lip it could be worn elsewhere and the only way to really know is to take multiple measurements with a bore gauge.... Link to comment Share on other sites More sharing options...
Colin Lindsay Posted February 20, 2020 Report Share Posted February 20, 2020 That's true and again it was a pleasure to watch an expert working on my block with ovality gauges etc to come up with a proper diagnosis. I'm the worst for letting engines soldier on with minimal attention to seals etc to address oil or water leaks, but this one was the first in a long time that I've had to work on and I couldn't just go the normal route of putting a replacement or recon engine in... I hope Hag gets away with minimal work required, but then I had hoped that too on this 1200 engine... Link to comment Share on other sites More sharing options...
Clive Posted February 20, 2020 Report Share Posted February 20, 2020 I read about using the 1200 pistons in the courier when one of the great Triumph chaps (Mr Thomason) of our time did the paris to peking rally. He used them.... Link to comment Share on other sites More sharing options...
Pete Lewis Posted February 20, 2020 Report Share Posted February 20, 2020 not forgetting the 1600 is a pretty unstressed unit did Mr T use the H pistons to quietly increase the designed capacity by a few CC ??? Pete Link to comment Share on other sites More sharing options...
Clive Posted February 20, 2020 Report Share Posted February 20, 2020 I think it was more about availability, even 20+ years ago 1600 stuff was tricky to find. But the extra capacity wouldn't hurt... Think he had a very low CR too, so as to cope with potentially rubbish fuel. But IIRC the fears were unfounded and he got the head skimmed during the event. Link to comment Share on other sites More sharing options...
haggis Posted February 21, 2020 Author Report Share Posted February 21, 2020 Just checked on rimmers website they Appear to have one set of +20’s for £600.00+vat. Link to comment Share on other sites More sharing options...
haggis Posted February 21, 2020 Author Report Share Posted February 21, 2020 But 1200’s are very available, cheap and increase the power so it’s a no brainier if it needs pistons. Thanks for all your help so far. hag Link to comment Share on other sites More sharing options...
Pete Lewis Posted February 21, 2020 Report Share Posted February 21, 2020 the only basic variance from 1600 to mk1 2ltr is the pistons all the rest is same as never understood the idea of hard to find 1600 stuff it never stopped me pete Link to comment Share on other sites More sharing options...
haggis Posted February 21, 2020 Author Report Share Posted February 21, 2020 Hi Pete, does that mean you could fit 2ltr mk1 Pistons in the 1600 block? thanks hag Link to comment Share on other sites More sharing options...
Pete Lewis Posted February 21, 2020 Report Share Posted February 21, 2020 i think there is a problem with the water jacket, think they have to rebore offset to avoid a thin walled cylinder but this is just from hearsay have no conclusive know how on the idea pete 1 Link to comment Share on other sites More sharing options...
ahebron Posted February 22, 2020 Report Share Posted February 22, 2020 There are a few sets of rings on Ebay https://www.ebay.com.au/itm/TRIUMPH-VITESSE-1600-1962-66-piston-ring-set-040/221664258154?hash=item339c38286a:g:KGgAAOSwYGFUuPcz https://www.ebay.com.au/itm/TRIUMPH-VITESSE-1600-1962-66-piston-ring-set-030/221664258139?hash=item339c38285b:g:H8AAAOSwYGFUuPbK Link to comment Share on other sites More sharing options...
Pete Lewis Posted February 22, 2020 Report Share Posted February 22, 2020 also canley have them to order https://www.canleyclassics.com/triumph-vitesse-1600-crankshaft-and-camshaft Pete Link to comment Share on other sites More sharing options...
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