timpress Posted January 10, 2022 Report Share Posted January 10, 2022 Hello, I removed my engine last night due to seriously low compression on no5 (went from 50 psi to 160 wet test) and before I send it off for checking and machining I thought I would ask about. As can be seen from the photos its a recessed type (confirmed by the strengthening brace above the sump) but as its got no engine stamp on it, anything I should be aware of as I assume it came out of another car, presumably not a TR6. Thanks Quote Link to post Share on other sites
John L Posted January 10, 2022 Report Share Posted January 10, 2022 I would check the piston top to the block face, the block may have been planned before perhaps, may be able to confirm if I knew what the recess depth should be, and any body confirm that dimension? John Quote Link to post Share on other sites
saffrontr Posted January 10, 2022 Report Share Posted January 10, 2022 In period engines without stamped numbers were supplied by the Factory to Distributors and Dealers as replacements for damaged blocks. The Distributors / Dealers were supposed to stamp the new block with the original engine number however it could be that this didin't always happen or it could be that the block that you have was just sold off unstamped when the Dealer / Distributor stopped selling Triumph cars. Derek Quote Link to post Share on other sites
timpress Posted January 10, 2022 Author Report Share Posted January 10, 2022 Thank you for the information. So much knowledge on here it is incredible! Quote Link to post Share on other sites
astontr6 Posted January 12, 2022 Report Share Posted January 12, 2022 On 1/10/2022 at 3:17 PM, John L said: I would check the piston top to the block face, the block may have been planned before perhaps, may be able to confirm if I knew what the recess depth should be, and any body confirm that dimension? John I would check the depth of the counter bores and find out what their usual depth is, as from the photos they look very shallow to me and not the correct depth? Bruce. Quote Link to post Share on other sites
timpress Posted January 16, 2022 Author Report Share Posted January 16, 2022 Hello again, after a little more information on my engine without any number stamped on it. Now I have the engine apart I find that the con rods and caps don’t have the corresponding numbers on them,1 through 6. They are just plain and unstamped. Anybody else come across this on theirs and anything I should be aware of when reassembling? thanks Tim Quote Link to post Share on other sites
john.r.davies Posted January 17, 2022 Report Share Posted January 17, 2022 Tim, I work on the Conrods of the engines I build, to lighten, polish and then shot peen them. This removes the old marks, but leaves them distinctly different looking! As above on the depth of the recess around the bore, skimming the block face to 'deck' the block may remove the stamped number. Any sign that yours has previously been rebuilt? Quote Link to post Share on other sites
timpress Posted January 17, 2022 Author Report Share Posted January 17, 2022 5 hours ago, john.r.davies said: Tim, I work on the Conrods of the engines I build, to lighten, polish and then shot peen them. This removes the old marks, but leaves them distinctly different looking! As above on the depth of the recess around the bore, skimming the block face to 'deck' the block may remove the stamped number. Any sign that yours has previously been rebuilt? It doesnt look like the bottom end has had any work on it but Ill take some photos of the rods to see if anyone sees any tell tale work such as lightening etc. Rings and crank bearings are all standard. The rings on pot 4 5 and 6 were all broken and fell away when removed. Glad Im doing the work as I dont think it would have lasted long and ran very badly. Quote Link to post Share on other sites
john.r.davies Posted January 17, 2022 Report Share Posted January 17, 2022 Here's a set of prepared conrods. Unlike the main beraing caps with have stamped numbers, these are usually numbers with a scriber, so easily removed. Quote Link to post Share on other sites
timpress Posted January 17, 2022 Author Report Share Posted January 17, 2022 3 hours ago, john.r.davies said: Here's a set of prepared conrods. Unlike the main beraing caps with have stamped numbers, these are usually numbers with a scriber, so easily removed. Mine definitely look stock but definitely have no numbers Quote Link to post Share on other sites
timpress Posted January 17, 2022 Author Report Share Posted January 17, 2022 Quote Link to post Share on other sites
timpress Posted January 17, 2022 Author Report Share Posted January 17, 2022 The bearings were 20thou so definitely had work but are scored badly. As can be seen by picture, rings fell off 4 of the pistons which were standard. Quote Link to post Share on other sites
BlueTR3A-5EKT Posted January 17, 2022 Report Share Posted January 17, 2022 As some one who sold many new recessed top blocks for 6 cylinder cars it could well have gone under my hand. They were supplied and we sold them without any engine number stamping as described in the factory letter. That was unless requested by the customer to stamp it. They were cheap too at £75.00. Same price as a new short back crank and cheaper than a rebore or thrust face rework. From memory, They did not come with all the screwed plugs fitted. Are your thrust washers loose and fall out when the main bearing cap is removed or are they pinned in place? That was a mod we offered to customers who were rectifying a thrust washer drop out that had wrecked their block and crank. Quote Link to post Share on other sites
john.r.davies Posted January 18, 2022 Report Share Posted January 18, 2022 10 hours ago, BlueTR3A-5EKT said: As some one who sold many new recessed top blocks for 6 cylinder cars it could well have gone under my hand. They were supplied and we sold them without any engine number stamping as described in the factory letter. That was unless requested by the customer to stamp it. But that letter required the Dealer to stamp the new block! "Require" (Specify as compulsory) leaves you no option to omit the stamping, unless the customer asked you not to! Quote Link to post Share on other sites
BlueTR3A-5EKT Posted January 18, 2022 Report Share Posted January 18, 2022 As we were not a franchised dealer the factory parts distribution centre that supplied us should have done it then, yr honour. Quote Link to post Share on other sites
timpress Posted January 18, 2022 Author Report Share Posted January 18, 2022 12 hours ago, BlueTR3A-5EKT said: As some one who sold many new recessed top blocks for 6 cylinder cars it could well have gone under my hand. They were supplied and we sold them without any engine number stamping as described in the factory letter. That was unless requested by the customer to stamp it. They were cheap too at £75.00. Same price as a new short back crank and cheaper than a rebore or thrust face rework. From memory, They did not come with all the screwed plugs fitted. Are your thrust washers loose and fall out when the main bearing cap is removed or are they pinned in place? That was a mod we offered to customers who were rectifying a thrust washer drop out that had wrecked their block and crank. I haven’t removed crank yet as I am waiting on a crank bolt socket to arrive but I’ll post up the results when I do remove it. Quote Link to post Share on other sites
harlequin Posted January 18, 2022 Report Share Posted January 18, 2022 May I suggest that you get someone with the correct type of micrometer to measure the rods and end caps to make sure that the bearing faces are round and if so mark up the matching paits. Rods and end caps were line bored in the factory and marked as they were intended to be paired for life, and if they are only a few thousand out of round the big end will nip up and wear. (I can't think of the name of the micrometer at the moment so maybe someone can remind me) George Quote Link to post Share on other sites
timpress Posted January 18, 2022 Author Report Share Posted January 18, 2022 3 hours ago, harlequin said: May I suggest that you get someone with the correct type of micrometer to measure the rods and end caps to make sure that the bearing faces are round and if so mark up the matching paits. Rods and end caps were line bored in the factory and marked as they were intended to be paired for life, and if they are only a few thousand out of round the big end will nip up and wear. (I can't think of the name of the micrometer at the moment so maybe someone can remind me) George Thanks for the suggestion. I haven't mixed any of the rods and end caps up after dismantling and have kept them as pairs. As the engine ran before dismantling, albeit with awful compression Im hopeful the rods and caps aren't going to be an issue. Quote Link to post Share on other sites
harlequin Posted January 18, 2022 Report Share Posted January 18, 2022 1 hour ago, timpress said: Thanks for the suggestion. I haven't mixed any of the rods and end caps up after dismantling and have kept them as pairs. As the engine ran before dismantling, albeit with awful compression Im hopeful the rods and caps aren't going to be an issue. I have recently done what you are undertaking at the moment, it all started with using lots of oil. My problem turned out to be a broken oil control ring which I am told is not uncommon with Grant rings. While I was doing this work I found a bad cam follower, which led on to a cam that was badly worn, when I started putting things back together with new big end bearings number 4 was very tight on the journal, on closer inspection I found the end cap was marked 2 (Rod 2 also had an end cap marked 2) so I inspected the old bearings and one set had worn eccentricity. I consigned Rod 4 with the mismatched cap to the scrap bin and used a good spare that I had. My engine was a rebuilt unit that came from Rimmers about 20 years ago which had ran fairly well , I guess I had been lucky when I ran the motor in. George Quote Link to post Share on other sites
cp25616 Posted January 20, 2022 Report Share Posted January 20, 2022 (edited) I once bought a brand new complete short motor from Unipart Express Factors in Swindon circa 1986, part number UKC 3596 if memory serves me correctly and it certainly did not have a number stamped on it. BL must have sold many like this, unstamped that is. It cost me £275 at the time, wish I had kept it now!! As well as the 1969 TR6 I bought back in 1991 it also had a brand new short motor in it when I bought it (still had the ally label attached) and it also was not stamped. Alan G Edited January 20, 2022 by cp25616 Quote Link to post Share on other sites
John L Posted January 20, 2022 Report Share Posted January 20, 2022 If you look closely at your con rod end there is a number above the hole for the bolt, its an electric tech, not a stamped number, they would have had to be etched/numbered when made to get the two parts together. John Quote Link to post Share on other sites
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