Nick Jones Posted October 31, 2011 Share Posted October 31, 2011 I've had the makings of a 2L short engine sat in the garage for a long time. The red beast has been getting in the way. Anyhow, I've finally got around to getting the bores re-honed, which has got me going again. The place that did that also gave the block a ride in their "dishwasher" to get rid of the honing grit. Today I've removed all the oil gallery plugs (some which were rather reluctant to move) and even the oil pump drive bush (see pic, don't often see them out!) to make sure there was nothing hiding behind that. It's pretty clean on the whole but did find a few lumps of crud behind plugs that hadn't been removed before. With the bush out you can see daylight through the main gallery (pic) I also had a poke around in the water jacket as these things are the very devil for silting up around the back of no 6. Didn't look bad, but just in case I poked a long screwdriver down the slot in the rear and tapped it with a hammer - which revealed that what looked like the bottom of the water jacket was in fact crud. A good inch of it in fact. You can see in the next pic a shelf to the right which marks the original "floor" height. There was a little in the front corner by no.1 as well but much less. Having had a good scrape and poke I then filled the water jacket with a warm phosphoric acid solution and left it for 45 mins. It fizzed a bit! Then about 10 rinses until it finally came clear and stopped spitting out lumps. I'm calling it clean now. Next job is to hunt down new plugs for the oil galleries. All seem to be available except the alloy one above the oil filter. Anyone know what the thread for that is? I'm also intending to use a conventional plug in the front of the main gallery rather than that aluminium thing. Otherwise there is an unused crank which has been balanced and hardened plus lightened and balanced rods. Block is zero decked. Have a duplex timing chain set (thanks Andy!) and a choice of cams....... Still teetering on the cam choice..... Not sure the current head has enough compression to make the more aggressive one work properly and I do like the "all-rounder" abilities of the original Mk2 cam...... Can't help thinking that with a fresh bottom end with a cam with 12 full lobes and the slightly higher compression from the zero deck we'll pick up a few horses anyway..... Nick Link to comment Share on other sites More sharing options...
GT6MK3 Posted November 1, 2011 Share Posted November 1, 2011 Nice one. Is this for "The Skip"? No temptation to skim the current head even a little? C. Link to comment Share on other sites More sharing options...
RealWorld Posted November 1, 2011 Share Posted November 1, 2011 ...finally got around to getting the bores re-honed, which has got me going again. I'm excited too. I still get a tingle whenever I, or anyone else, starts a 'build'. Maybe I'm just weird. R Link to comment Share on other sites More sharing options...
Nick Jones Posted November 1, 2011 Author Share Posted November 1, 2011 Nice one. Is this for "The Skip"? No temptation to skim the current head even a little? C. This head started as a 2.5L S one. It's also had some chamber work (bad idea probably) so it has already had a MAMMOTH skim and anymore carries a big risk of finding water or oil (the edge under the plugs is real thin already). Should give about 10.3:1 static CR, which is probably ok for the standard cam but a bit light for the hotter one. Nick Link to comment Share on other sites More sharing options...
GT6MK3 Posted November 1, 2011 Share Posted November 1, 2011 This head started as a 2.5L S one. It's also had some chamber work (bad idea probably) so it has already had a MAMMOTH skim and anymore carries a big risk of finding water or oil (the edge under the plugs is real thin already). Nice. Dont think the 2.5 S was ever sold in Aus, but the Chris Witor articles reckon it's the daddy of all heads for flow. I'll be bobbing up before too long with questions about tolerances of various heads for skimming, haven't been able to get my google noodle around whether the 2.0 were just skimmed harder at the factory than the 2.5, or if the 2.5's were designed with the passages lower and more susceptible to skim damage. Prepare for a barrage of questions... C. Link to comment Share on other sites More sharing options...
James Posted November 1, 2011 Share Posted November 1, 2011 My new head is from a GT6 Mk2 and it's been skimmed to almost 11:1 — it has plenty of meat left. I seem to remember someone mentioning that the 2 litre heads were cherry picked from the 2.5 heads — so safer to skim. Link to comment Share on other sites More sharing options...
Nick Jones Posted November 1, 2011 Author Share Posted November 1, 2011 My suspicion is that the earlier 2L heads for the flat piston engines are in fact a slightly different casting. Certainly they seem to have more meat on the ledge under the plugs. I do still have my "development" head which is based on a Mk2 Vitesse head - but would need guides, inserts, valves, springs etc. Nick Link to comment Share on other sites More sharing options...
GT6Steve Posted November 1, 2011 Share Posted November 1, 2011 It's always been said that the Circle B heads are the ones to build on. There's an article floating around that MAY be from Witor detaing casting numbers to use. I've always used whatever I had as beggars can't usually be choosers.... Link to comment Share on other sites More sharing options...
Mark Posted November 1, 2011 Share Posted November 1, 2011 Whilst renewing the core plugs on the Vitesse, and poking around number six cylinder clearing all the old sludge out, I fished this out, a crushed core plug Somebody in the distant past must have belted it in and couldn't be bothered to retrieve it before fitting another core plug. The ladyI bought the car from had owned it since 1971 and said she always had it serviced at a local garage. Could't have helped with the cooling. Mark Link to comment Share on other sites More sharing options...
toofast2race Posted November 2, 2011 Share Posted November 2, 2011 I have both those plugs in alloy if you want them for a beer next 10CR Link to comment Share on other sites More sharing options...
Nick Jones Posted November 2, 2011 Author Share Posted November 2, 2011 I have both those plugs in alloy if you want them for a beer next 10CR Thanks Andy - I think I've tracked them all down now. The one above the oil filter is going to be a length of 3/4" UNF bolt as per your previous CT post! The previously alloy one at the front of the main gallery is going to a short steel plug. Cheers Nick Link to comment Share on other sites More sharing options...
GT6Steve Posted November 2, 2011 Share Posted November 2, 2011 If we're talking about the plugs around the oil filter why not simply tap them for 3.4 NPT now and plug them with a standard pipe plug. Then should you want an oil cooler or external filter the machine work is already done and waiting? I like the plugs with a hex recess but they are harder to find than the square peg style. Thanks Andy - I think I've tracked them all down now. The one above the oil filter is going to be a length of 3/4" UNF bolt as per your previous CT post! The previously alloy one at the front of the main gallery is going to a short steel plug. Cheers Nick Link to comment Share on other sites More sharing options...
Nick Jones Posted November 3, 2011 Author Share Posted November 3, 2011 If we're talking about the plugs around the oil filter why not simply tap them for 3.4 NPT now and plug them with a standard pipe plug. Then should you want an oil cooler or external filter the machine work is already done and waiting? I like the plugs with a hex recess but they are harder to find than the square peg style. Err, 'cause I don't have 3/4" BSP tap or a drill that big (or even anything that will spin a drill that big ). Anyway, a 3/4" UNF bolt cut down to size and loctited will do just fine. Thanks to Andy T for that tip I like the hex recess ones best as well and they took some finding here too. However, I did manage to buy them over the counter right here in sleepy Yeovil....... though not all at the same counter. They make helicopters in this town..... may count for something.... Next thoughts: When I did my Herald 1300 many years ago, the block got tanked and came back utterly naked. So I painted it inside and out. Red oxide primer everywhere, then something green on the outside only. The red oxide was still there 6 or 7 years later when I had cause to venture in there again. Although thoroughly cleaned (several times now)this block has not been tanked. Therefore quite a bit of of the original internal paint remains. I suspect I'll take the lazy way and leave it like that, not least because I'd be a bit suspicious of new paint sticking properly to the old. Anyone have any strong opinions/advice on the subject? Nick Link to comment Share on other sites More sharing options...
Martin Posted November 21, 2011 Share Posted November 21, 2011 Hi Nick, any recommendation how to get the front end plug of the oil gallery out of the block? Dilling?? Seems to be alloy. It is flat with the surface of the block. Martin Link to comment Share on other sites More sharing options...
Nick Jones Posted November 21, 2011 Author Share Posted November 21, 2011 I drilled a hole in it (approx 5mm) so I could knock a Torx driver tightly into the hole and use that to undo it. Worked well. used the same technique on the larger one above the oil filter and some of the smaller gallery plugs where the steel plugs were already damaged. Nick Link to comment Share on other sites More sharing options...
Martin Posted November 21, 2011 Share Posted November 21, 2011 ... the one above the oil filter resists I started with T30 now I´m at T50 and it does not move, oh only the alloy itself ... Have to start to poke it out somehow .... Martin Link to comment Share on other sites More sharing options...
GT6Steve Posted November 21, 2011 Share Posted November 21, 2011 That one is always a bugger to get out. I assume it was hammered in. When you get it moving you'll find threads or maybe ridges cut in the block to provide grip for the alloy. Even drilling it is a turd cuz the cast iron seems to cut easier than the alloy! ... the one above the oil filter resists I started with T30 now I´m at T50 and it does not move, oh only the alloy itself ... Have to start to poke it out somehow .... Martin Link to comment Share on other sites More sharing options...
Nick Jones Posted November 21, 2011 Author Share Posted November 21, 2011 Mine came out without much aggro. Probably used about an 8mm hole and appropriate Torx bit on that one. There is a proper 3/4" UNF thread under it. The plugs come as sticks of 9 . Screw in, snap off and peen over. Nick Link to comment Share on other sites More sharing options...
GT6Steve Posted November 21, 2011 Share Posted November 21, 2011 Well that's interesting. Are the plug sticks available or is that news from the day? I'd love to see one. Mine came out without much aggro. Probably used about an 8mm hole and appropriate Torx bit on that one. There is a proper 3/4" UNF thread under it. The plugs come as sticks of 9 . Screw in, snap off and peen over. Nick Link to comment Share on other sites More sharing options...
toofast2race Posted November 21, 2011 Share Posted November 21, 2011 Well that's interesting. Are the plug sticks available or is that news from the day? I'd love to see one. Roadster factory sells them: http://trf.zeni.net/TR6bluebook/15.php?s_wt=1920&s_ht=1080#AH11 AH8 and AH11 Link to comment Share on other sites More sharing options...
Nick Jones Posted October 20, 2013 Author Share Posted October 20, 2013 Thread revival time........ I'm now actually in a position to get on with this with some chance of finishing it! Block machining work is all done - it is not the one I started the thread with due to issues with inept cam bearing boring. It's a late ribbed block originally from a 2500S. Cam bearings are fitted (the cam goes round and the bearings stay put this time!). It's been skimmed to remove the fire ring recesses and this has left me with some piston pop-up. 1 = 0.014" 2 = 0.0128" 3 = 0.0126" 4 = 0.0095" 5 = 0.011" 6 = 0.016" I wouldn't mind some pop up (need the compression and not much left on the head), but that is too much I think. If they'd all been under 0.010" I'd probably have just left it, but as it is I'm intending to get the pistons skimmed to give me an even 0.005". Off to the machine shop tomorrow. Today, after careful measuring with DTI to get the above info, I've cleaned out the water jacket (loads of silt!) and fitted new core plugs. Now need to clean out the oil ways and refit the gallery plugs and oil pump/dizzy drive bush. Then, once the pistons are back I can put it all together. It's only been about 4 years so far! Nick Link to comment Share on other sites More sharing options...
GT6MK3 Posted October 20, 2013 Share Posted October 20, 2013 Are you planning to mod the oil galleys at all? C. Link to comment Share on other sites More sharing options...
GT6Steve Posted October 20, 2013 Share Posted October 20, 2013 Good job Amigo, I was thinking of the exact same question. Seeing as how Nick may have nailed the problem with our engines I wondered what the plans were... Link to comment Share on other sites More sharing options...
Triumph-V8 Posted October 21, 2013 Share Posted October 21, 2013 I wouldn't mind some pop up (need the compression and not much left on the head), but that is too much I think. If they'd all been under 0.010" I'd probably have just left it, but as it is I'm intending to get the pistons skimmed to give me an even 0.005". Off to the machine shop tomorrow. Nick Unfortunately the pistons come out of the block a bit more when engine is off throttle at high revs. Had to learn that my Lotus engine did that by 0.4mm. I did the job on a lathe step by step for each piston made a holder from a round steel peace to get all things rectangular. Link to comment Share on other sites More sharing options...
GT6MK3 Posted October 21, 2013 Share Posted October 21, 2013 Good job Amigo, I was thinking of the exact same question. Seeing as how Nick may have nailed the problem with our engines I wondered what the plans were... Yep, Im curious 'cos I'm picking up by "hamburger with the lot" block tomorow after it's second round of honing. Time to stop playing with the van and get back to building my engine. C, Link to comment Share on other sites More sharing options...
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