russ01 Posted April 22 Report Share Posted April 22 Hi everyone I have a 1968 triumph herold 13/60 . Runs fine on tic over with Rocker cover breather pipe removed from air filter housing, but as soon as it is re connected the engine slows and then stalls . If the breather pipe is connected on a relatively short run it develops a miss fire and eventually cuts out all together, every time sooting up the plugs could this be due to lack of valve clearance?(I have noticed that there is no tapping whatsoever that I can hear) Thanks in advance for any advice Link to comment Share on other sites More sharing options...
johny Posted April 22 Report Share Posted April 22 It sounds as if your carb mixture is set very rich so that it runs ok when extra air is introduced via the open breather pipe. This would account for the sooting up when the pipe is connected. Cant see the tappets having this effect although of course as always if you have any doubt over their setting they should be checked... 1 Link to comment Share on other sites More sharing options...
russ01 Posted April 22 Author Report Share Posted April 22 (edited) Thanks Johny . I did think running rich but was just an extra thought as it seemed strange not to hear the tappets tapping away, and there did seem to be more than usual gases coming from the breather pipe. Also all I need to do is hold the breather pipe near to the air filter housing connection point for it to slow the tickover to the point of the engine stalling. My thinking was if valves not quiet sealed and allowing exhaust gas and fuel to be pushed past the valves and out the rocker cover breather . I will be checking both as soon as it stops raining as I don't have anywhere under cover to work on it ATM. Just looking for thoughts and opinions before I get into it and start going down the rabbit hole and end up replacing/repairing things I don't need to lol Edited April 22 by russ01 Link to comment Share on other sites More sharing options...
DanMi Posted April 22 Report Share Posted April 22 If the valves were not closing the gases would exit via the manifolds not the rocker cover. If there is excessive gas coming from the breather, that would indicate excess gases entering the crank case, maybe worn/broken piston ring. I would do a compression check 1 Link to comment Share on other sites More sharing options...
russ01 Posted April 22 Author Report Share Posted April 22 (edited) Thanks DanMi that would make sense I'll have to see if I can borrow a compression tester Edited April 22 by russ01 Link to comment Share on other sites More sharing options...
johny Posted April 22 Report Share Posted April 22 Yes it sounds like you might have a lot of fumes coming from the breather pipe and I go with the explanation above. Is the car new to you as I wonder if a previous owner has set it up to run with the pipe disconnected😲 As well as the compression check suggested I would adjust the mixture to the standard setting in the manual and then try reconnecting the pipe. If it runs then you can fine tune the mixture... 1 Link to comment Share on other sites More sharing options...
russ01 Posted April 22 Author Report Share Posted April 22 Yes the car is new to me. I'll check the compression, if compression is low I think the car will end up going back to the previous owner as I only picked it up yesterday ☹️ 1 Link to comment Share on other sites More sharing options...
Pete Lewis Posted April 22 Report Share Posted April 22 its also worth checking no filter gaskets are obstructing the front face ports of the carbs there should be inside the rocker cover a metal gauze needs the retainer prizing open to extract it and wash in petrol a check of the diaphragm is worthwhile if its wrinkled a wash in petrol will revert it to size the diaphragm has location lugs to correctly position the air piston when was the filter last changed ??? as for mixture from level with the jet housing 3 turns down is a good start setting tight valve clearances do have a big effect on idle quality 1 Link to comment Share on other sites More sharing options...
russ01 Posted April 22 Author Report Share Posted April 22 I'm going to my local garage this afternoon going to test emitions hopefully will give a bit more idea as to what is going on, will possibly test what is coming from breather pipe as well Link to comment Share on other sites More sharing options...
russ01 Posted April 22 Author Report Share Posted April 22 Well managed to do a bit more investigation at the garage and it's looking piston rings need replacing ☹️ Thanks for your help everyone . Link to comment Share on other sites More sharing options...
johny Posted April 22 Report Share Posted April 22 Glad youve got an answer and bear in mind that its not just the rings that wear but also the bores so it may need a rebore and new pistons which unfortunately adds considerably to the costs... Link to comment Share on other sites More sharing options...
Pete Lewis Posted April 22 Report Share Posted April 22 has the car stood for ages rings can get gummed up with lack of use . often a good dose of redex in the plug hole and left for a few days can make a cheap improvement but will make clouds of smoke when you restart it Pete Link to comment Share on other sites More sharing options...
russ01 Posted April 22 Author Report Share Posted April 22 I've managed to source a complete engine carb and all that came out of a good runner that has a chassis that is rotten and not really viable to repair. At least that way I'll have a car that runs and an engine that I can rebuild at leisure and a few extra spares to boot Link to comment Share on other sites More sharing options...
Colin Lindsay Posted April 23 Report Share Posted April 23 14 hours ago, russ01 said: I've managed to source a complete engine carb and all that came out of a good runner that has a chassis that is rotten and not really viable to repair. At least that way I'll have a car that runs and an engine that I can rebuild at leisure and a few extra spares to boot Keep all the spares you can, parts are becoming ever more rare and very expensive. 1 Link to comment Share on other sites More sharing options...
daverclasper Posted April 25 Report Share Posted April 25 On 22/04/2024 at 18:27, Pete Lewis said: often a good dose of redex in the plug hole and left for a few days can make a cheap improvement After this, though maybe a be a good idea to turn the engine over before fitting plugs, as if the Redex hasn't drained down from the piston top, then could hydraulic the engine? Link to comment Share on other sites More sharing options...
russ01 Posted April 25 Author Report Share Posted April 25 Did a compression test today number 3 only about 10psi all others around 75psi . Put a good glug of redex down the plughole, will give it another test in a few days before I do the engine swap. If no improvement will strip it down and have a look once the replacement engine is in Link to comment Share on other sites More sharing options...
JohnD Posted April 25 Report Share Posted April 25 Which explians the sooty plugs and poor running. 1 Link to comment Share on other sites More sharing options...
DanMi Posted April 26 Report Share Posted April 26 22 hours ago, russ01 said: Did a compression test today number 3 only about 10psi all others around 75psi . Put a good glug of redex down the plughole, will give it another test in a few days before I do the engine swap. If no improvement will strip it down and have a look once the replacement engine is in did you retry after putting a squirt or 2 of oil in the cylinders, if the readings increase a lot that would mean bad rings as we suspect, if they don't go up at all it is valves. I would check the valve clearances before you repeat the compression check anyway Link to comment Share on other sites More sharing options...
russ01 Posted April 26 Author Report Share Posted April 26 No I didn't I've not had chance, I had to cover it up because it started chucking it down. I will try again before I take the engine out Link to comment Share on other sites More sharing options...
Colin Lindsay Posted April 27 Report Share Posted April 27 On 22/04/2024 at 10:00, russ01 said: Hi everyone I have a 1968 triumph herold 13/60 . Forgive me for finding that funny... it struck a chord with me as my own 1200 was advertised as a Trumiph Herlad and the cars in our house are now all referred to as 'Trumiphs'. Link to comment Share on other sites More sharing options...
russ01 Posted April 27 Author Report Share Posted April 27 (edited) Well I re did the compression test today with a bit of oil down the offending plug hole no difference, so I set the tappets an re tested I now have around 45psi still a way of the rest. Now my question is could it be the fact that the valves have not been fully closing for a long time that there is a build up of carbon on the offending valve and valve seats causing the valves to still not creating a good seal or a combination of incorrect valve clearance and worn piston rings ????? Edited April 27 by russ01 Link to comment Share on other sites More sharing options...
johny Posted April 27 Report Share Posted April 27 (edited) If it was an exhaust valve it may have been burnt. However what happened to the other readings, did they come up to the desired 120psi+? Edited April 27 by johny Link to comment Share on other sites More sharing options...
russ01 Posted April 27 Author Report Share Posted April 27 To be honest I've had bit of a long day today so just concentrated on the one with 0 compression, but that said seen as all the valves had 0 clearance I'm guessing that the others will have improved. I will check compression on All cylinders next week when I have more time and I don't feel like someone has tried to rip my spine out lol Link to comment Share on other sites More sharing options...
Pete Lewis Posted April 27 Report Share Posted April 27 there a chance that the tight clearances will have caused the seats to be burnt no easy way to test and probably needs the head off for a look Pete Link to comment Share on other sites More sharing options...
russ01 Posted April 27 Author Report Share Posted April 27 Yes I can strip it down at my leisure once I have done the engine swap, I will possibly do a full rebuild when cashflow allows Link to comment Share on other sites More sharing options...
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