RogerH Posted April 4, 2016 Author Report Share Posted April 4, 2016 Hi Folks, been very busy this morning. I had an idea about using the milling machine to help with the measuring - hold the DTI in the chuck and the bad is square. Everything should line up. No it doesn't. After about 2 hours of measuring and machining i came to the conclusion that nothing was square or parallel. So I popped into the machine shop I should have used in the first place and they will refurbish. As the man said - if it is still a little out we can replace the little end bush and ream parallel to the big-end. Hopefully that is ouit of the way - I can now get on with the rest of the car. Roger Quote Link to post Share on other sites
Don H. Posted April 4, 2016 Report Share Posted April 4, 2016 ...So I popped into the machine shop I should have used in the first place... Best news I've heard today, Roger. Well done! Quote Link to post Share on other sites
barkerwilliams Posted April 4, 2016 Report Share Posted April 4, 2016 Roger, if you had £260 going spare then http://www.maxspeedingrods.co.uk/high-performance-triumph-tr3-tr4-4340-en24-chrome-moly-forged-h-beam-connecting-rods-conrod-with-arp-bolts-x4pcs.html Alan Quote Link to post Share on other sites
RogerH Posted April 4, 2016 Author Report Share Posted April 4, 2016 Hi Alan, I was looking at them last night. There was a post on the CT forum a few months back and the general view was they were very good value for money. However I would probably have to have the crank etc re-balanced as they look a lot lighter than the ST hunks. The workshop think they can sort my curly wurly rods. Roger Quote Link to post Share on other sites
Lebro Posted April 4, 2016 Report Share Posted April 4, 2016 Is this the "Like to take our time" workshop ? Bob. Quote Link to post Share on other sites
barkerwilliams Posted April 4, 2016 Report Share Posted April 4, 2016 Roger, I bought a set a few months ago for my TR6. I'm building up a stock of parts for a rebuild at the end of this year. They look very, very nice. Well finished and at about £50 a piece; cheaper than "original" style rods from the usual sources. Alan Quote Link to post Share on other sites
RogerH Posted April 4, 2016 Author Report Share Posted April 4, 2016 Hi Bob, I've gone back to C&M in Bracknel. Roger Quote Link to post Share on other sites
TriumphV8 Posted April 4, 2016 Report Share Posted April 4, 2016 (edited) I bought a set a few months ago for my TR6. I'm building up a stock of parts for a rebuild at the end of this year. They look very, very nice. Well finished and at about £50 a piece; cheaper than "original" style rods from the usual sources. Agree to that, I have them modified with my VW pistons. New bronze small ends to suit the 17mm VW gudgeon pin and excentric to extend length of the rod. These are reamed rectangular on the milling machine. In the picture is also the modified old rod to suit the Mazda 78mm piston As the TR4 and TR6 cranks are balanced in itself they work properly with the lighter rods without rebalance. It can be a idea to remove weight from the counterweight for lighter rods and rebalance than but that is not worth the effort. Compared to the heavy price of the Carillos they are a bargin. Edited April 4, 2016 by TriumphV8 Quote Link to post Share on other sites
RogerH Posted April 6, 2016 Author Report Share Posted April 6, 2016 (edited) Hi Folks, the engine saga has taken on another twist. Firstly I have the rods back from the machine shop and they found that all the small ends were on the slant - probably poor interpretation by the receptionist But the new small ends have been reamed parallel to the Big-ends and having tried one it looks good. Now for the twist. I was preparing to build up the head when I noticed a black mark on #4 inlet valve seat. Sure enough it is a crack - I know about cracks having done 36 years hunting the bu99ers down. After a bit of investigation the crack goes down further than an insert would go. The proper machine shop (C&M is Bracknell) confirmed this and declared the head scrap. They were amazed that the other machine shop didn't crack test the head before starting the machining - this could cause some feathers to fly - new guides, time etc. Having found this problem I have decided to pull the crank (bu99er bu99er bu99er) and get it balanced. At least I will know for certain the condition. Had speaks with Moss this morning and a new head will be apprx £1600 (the price of a TR6 in 1973), they have a couple ion stock, fully built. It's only money and you can't take it with you. However I know where I would like to stick the cracked head. Roger Edited April 6, 2016 by RogerH Quote Link to post Share on other sites
Don H. Posted April 6, 2016 Report Share Posted April 6, 2016 Roger, I'm not paying the bills, but your news is very encouraging. You're on the right track now! Quote Link to post Share on other sites
TriumphV8 Posted April 6, 2016 Report Share Posted April 6, 2016 Roger, very sorry for that! It is not uncommon for heads with seat rings that they crack between IN and EX. That is why I avoid seat rings in my TR6 because already my old TR6 with the bigger exhaust valves had a crack there. So I think that was the real reason for Triumph to swap to the smaller exhaust in the newer TR6 to have a bit more material in that area. As we do not have to pay for labour it might be an idea to weld the head with a nickel elektrode and fit a seat ring for inlet, too. Do not know if TIG welding is possible but the access to the tungsten tip is very good in the inlet. Maybe worth a try before buying a new one! Quote Link to post Share on other sites
RogerH Posted April 6, 2016 Author Report Share Posted April 6, 2016 Hi Don, having found the cracked seat I had a sudden feeling of relief because now my hand is forced to get it all done properly. I was racing against various time schedules - most of them have now gone by. So the main thing is to get the engine and car up and running for the end of May for my big Scottish tour. Hi Andreas, I have had dabblings with Ali/Nickel/bronze and it can work. The heat in the inlet tract is not as high as the exhaust so could be achievable. However time is not on my side - so I shall bite the bullet and buy a new head (either for the car or for me) and then consider a repair at my leisure. Tomorrow the crank will be at the workshop to be balanced (assessed) - the result should be interesting. Roger Quote Link to post Share on other sites
Lebro Posted April 6, 2016 Report Share Posted April 6, 2016 Yes, I was wondering if that crack was there prior to fitting the exhaust valve seat. Bob. Quote Link to post Share on other sites
RogerH Posted April 6, 2016 Author Report Share Posted April 6, 2016 Hi Bob, the head was unleaded in apprx 2000 and I'm sure C&M did it. They crack test their heads before machining. Roger Quote Link to post Share on other sites
LGFromage Posted April 6, 2016 Report Share Posted April 6, 2016 Hi Roger, The cylinder head on my 4A had a nasty water jacket hole at number 4 spark plug which was welded up by this company: http://www.castironweldingrepairs.co.uk/. They did a great job in a difficult area at a price significantly cheaper than a new head. I suggest that a cracked valve seat would be a more straightforward job (based on previous experience of on a different engine) and hence cheaper. You should note that the whole head is heated to a high temperature for which the push rod tubes are removed. Take care of the tubes as they need to be re-fitted afterwards - new ones are 22thou larger in diameter. Good luck. Tim Quote Link to post Share on other sites
RogerH Posted April 6, 2016 Author Report Share Posted April 6, 2016 Hi Tim, thanks for that. I think I will go for the new head but investigate these people and get the head sorted in a decent time frame. Roger Quote Link to post Share on other sites
RogerH Posted April 7, 2016 Author Report Share Posted April 7, 2016 Well Folks, I've well and truly bitten the bullet. I now own a new TR4A cylinder head. I have decided to mount it on top of the bonnet or have the bonnet made of Perspex. I popped the crank and bits into the workshop this morning to have it re-balanced. The head man gasped when he saw it. I hope it is OK - there aren't many cranks like this one about. Roger Quote Link to post Share on other sites
Richard71 Posted April 7, 2016 Report Share Posted April 7, 2016 Well Folks, I've well and truly bitten the bullet. I now own a new TR4A cylinder head. I have decided to mount it on top of the bonnet or have the bonnet made of Perspex. I popped the crank and bits into the workshop this morning to have it re-balanced. The head man gasped when he saw it. I hope it is OK - there aren't many cranks like this one about. Roger C'mon then Roger, a pic or two of the new cyl head then! Quote Link to post Share on other sites
RogerH Posted April 7, 2016 Author Report Share Posted April 7, 2016 Hi Richard, it looks just like an old head but cleaner. I think it may be made from gold. Roger Quote Link to post Share on other sites
TorontoTim Posted April 8, 2016 Report Share Posted April 8, 2016 Gasped in a good way...? Quote Link to post Share on other sites
RogerH Posted April 8, 2016 Author Report Share Posted April 8, 2016 Hi Tim, I think it was a gasp as in 'Oh Sh*t. Roger Quote Link to post Share on other sites
acaie Posted April 9, 2016 Report Share Posted April 9, 2016 Hi Richard, it looks just like an old head but cleaner. I think it may be made from gold. Roger Is this comment based on the price? Quote Link to post Share on other sites
RogerH Posted April 9, 2016 Author Report Share Posted April 9, 2016 Yes. Roger Quote Link to post Share on other sites
Alec Pringle Posted April 9, 2016 Report Share Posted April 9, 2016 He turned up offering two pints of lager and a packet of crisps . . . . even the offer of a third pint didn't alter the SHED ! response . . . . That's when the credit card got torpedoed . . . . . Strictly camping, not B&B, for the rest of this year . . . . . Cheers Alec Quote Link to post Share on other sites
RogerH Posted April 21, 2016 Author Report Share Posted April 21, 2016 Hi Folks, good news - the crank is ready for collection. All went well. Perhaps I can now get on with assembling the engine once and for all. Roger Quote Link to post Share on other sites
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