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Post by JohnV on Jun 14, 2020 15:37:34 GMT
glad it was a simple fix Andrew ....... top man Tony
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Post by Deleted on Jun 14, 2020 16:23:22 GMT
It's really made my day. I can't believe the amount of noise caused by it. It was really loud!
I know how engines work but never really been into the hands on thing so i was getting worried it was serious.
Just been out for sea trials and some engine loading and it's fine. Running lovely.
That's without even using feeler gauges -just leaving a little clicky gap- as I don't have any feeler gauges on the boat. I will get some on there and do it all exactly right.
Very pleased about this.
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Post by Isambard Kingdom Brunel on Jun 14, 2020 17:08:13 GMT
May be worth setting the tappets on the other engine too...................................................... It is part of the routine service on a BMC, along with re-torquing the heads down....................................... I'm reluctant to touch the other unit as it is 100% and no smoke once running. Remarkably good unit actually all I want to do is be naughtyfox on that one. Do you think it will run well for ever without the recommended maintenance? I don't know naughtyfox.
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Post by JohnV on Jun 14, 2020 17:29:56 GMT
I'm reluctant to touch the other unit as it is 100% and no smoke once running. Remarkably good unit actually all I wbyou think it will run well for ever without the recommended maintenance? I don't know naughtyfox. but naughty fox doesn't have an engine, he has a funny little red thing that pretends to be an engine, making a funny little noise and using vast amounts of lubricating oil.
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Post by Deleted on Jun 14, 2020 17:30:55 GMT
I'm reluctant to touch the other unit as it is 100% and no smoke once running. Remarkably good unit actually all I want to do is be naughtyfox on that one. Do you think it will run well for ever without the recommended maintenance? I don't know naughtyfox. naughtyfox is well known for changing his engine lube oil at regular intervals. Depending on the current OCD level this can be as low as 8 hours between changes. I would probably go for more like 100 myself. Something I have never done before that often but I think regular (socially distant) oil changing is probably a wise plan. Other than that the port side power unit don't need messing with on this boat. Apart from learning about the tappets today I also discovered they start without heater plugs at tickover at this time of year. Never realised that. I always thought heat was needed for these. Not so.
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Post by JohnV on Jun 14, 2020 17:31:59 GMT
BMC's like to be cosseted (and also like to be kept cool)
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Post by Deleted on Jun 14, 2020 17:34:12 GMT
BMC's like to be cosseted (and also like to be kept cool) They both sit at just under 70 degrees on the keel coolers no concerns there at all. Direct cooling via welded channels on the hull. Dealt with. I'm glad to lose that knock it was really disturbing. No damage to any of the push rods or tappets as I have not used it in anger since the knocking started. Will be keeping an eye on it anyway. Lovely pair of engines actually from the serial numbers they appear to be ex Austin J4 police van units with PRM delta boxes on. All custom marinised and installed by the man who made the boat. And very nicely done too. My anxiety problems were quite severe about this I really thought I might be looking at a shot engine while not quite believing it.
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Post by naughtyfox on Jun 14, 2020 17:49:23 GMT
This is not ours, but you get the general idea:
Last time I changed the engine oil was in October. Christmas trip & February trip couldn't leave marina due to the Kennet level. Still, the engine has been started twice this past week and had a little 10-minute run each way, so it's good to 'stand' for another 3 months if I/we can't get over.
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Post by Deleted on Jun 14, 2020 17:56:08 GMT
It's a lovely little unit for a small narrow boat. You would be hard pressed to find a better one.
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Post by TonyDunkley on Jun 15, 2020 3:55:24 GMT
Exactly what happened to mine, a sort of chuffing knock sound through the air intake. I've been putting a bit of acetone in with the diesel, 100ml. This has resulted in almost eradicating the issue, slowly but surely. So I'm assuming a bit of gum between valve and seat, or gummed up injector. The addition of some Acetone to the fuel will almost certainly have been effective to some extent in shifting carbon deposits and gum out of the injector nozzles, but I'd be very wary of continuing to use it as a fuel additive, or of using it again if the same valve trouble symptoms return. It's a very effective solvent which will eventually dissolve most things, . . and unfortunately that's very likely to include seals and some components in the injector pump and/or fuel system ! There is also a possibility that the addition of acetone could affect the lubricating properties of diesel fuel and increase the rate of pump wear. The fuel it's sending to the injectors is the only source of lubrication the close tolerance high pressure pumping and metering components in the injection pump get. Proprietary brands of injector cleaner - Wynns, Holts, Gunsons, and the like - stocked in the motoring sections of the big supermarkets is quite effective and won't do any harm if used in the recommended doses, . . but make sure it's the stuff for diesel fuel systems and not the sort intended for the petrol fuel injection systems found on cars.
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Post by Deleted on Jun 15, 2020 5:20:38 GMT
There are a couple of bottles of "Starbrite" diesel additive on the boat. They are quite old. I wonder if this stuff has a shelf life. I've not used any since adding fuel to the tanks myself.
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Post by naughtyfox on Jun 15, 2020 6:35:41 GMT
"Knock, knock!"
"Who's there?"
"BMC 1.5"
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Post by TonyDunkley on Jun 15, 2020 7:21:56 GMT
There are a couple of bottles of "Starbrite" diesel additive on the boat. They are quite old. I wonder if this stuff has a shelf life. I've not used any since adding fuel to the tanks myself. and on 14 June 2020 :Just a quick check shows you are spot on here Sir. I can already see two tappets with about 1/8 inch clearance or more. Obvious question is how did they get that far out?? and :I'm reluctant to touch the other unit as it is 100% and no smoke once running. Depending on their age, those bottles of fuel additive may have lost some of their potency, but I wouldn't expect them to be in any way harmful to your engines or fuel system. I think the worst that could result from using them would be not achieving their primary intended purpose of restoring the Cetane Number/ignition quality of the treated fuel to the original values when it was fresh from the refinery. With regard to the excessively loose tappets/valve clearances you found on the 'knocking' engine, I have to say that it was quite the opposite of what I thought you might find, and my expectation was for you to find several valves and tappets with little or no clearance at all, . . not uncommon with marine engines brought back into use after long lay-up periods, and almost invariably as a result of the valves settling deeper into their seatings than before as the engine rids itself of carbon particles and corrosion accumulating on and around the seatings of any valves that were open or partially open during the lay-up period. There is a possibility that the 1/8" or more clearances you found could be the result of bent pushrods. Clumsy re-assembly and tightening down of the rocker shaft and pedestals can put a slight bend in pushrods that aren't properly lined up and engaging their cups in the ball-ends of the tappet adjustment screws in the rockers. The strains of subsequent running then gradually increase the initial slight bend in any affected pushrods, and the valve clearances gradually open up on a par with the increasingly bent pushrods. As for the other engine - the quieter one of the two - although it's starting easily and running clean at present, there is a distinct 'off' beat detectable in the sound clip you posted yesterday, and I don't think it should be ignored. Judging from how both engines started and ran from cold without pre-heat, I reckon you've got a couple of really sound engines with nigh on perfect bores, rings, pistons, and valves, and it would be a pity to risk ruining either of them for the sake of a few simple checks and some routine maintenance. My advice is that, at the very minimum, you get a set of feeler gauges and adjust the tappets on both engines. I would also urge you to have all the pushrods out of both engines, one by one ensuring they all go back in the same location, and check that they're straight, . . . before adjusting the tappets ! It's a simple and relatively quick job to do, and it doesn't involve any major dismantling. If you're unsure about any aspect of it, I can talk you through the job over the phone whilst you're doing it.
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Post by Deleted on Jun 15, 2020 8:04:20 GMT
Exactly what happened to mine, a sort of chuffing knock sound through the air intake. I've been putting a bit of acetone in with the diesel, 100ml. This has resulted in almost eradicating the issue, slowly but surely. So I'm assuming a bit of gum between valve and seat, or gummed up injector. The addition of some Acetone to the fuel will almost certainly have been effective to some extent in shifting carbon deposits and gum out of the injector nozzles, but I'd be very wary of continuing to use it as a fuel additive, or of using it again if the same valve trouble symptoms return. It's a very effecting solvent which will eventually dissolve most things, . . and unfortunately that's very likely to include seals and some components in the injector pump and/or fuel system ! There is also a possibility that the addition of acetone could affect the lubricating properties of diesel fuel and increase the rate of pump wear. The fuel it's sending to the injectors is the only source of lubrication the close tolerance high pressure pumping and metering components in the injection pump get. Proprietary brands of injector cleaner - Wynns, Holts, Gunsons, and the like - stocked in the motoring sections of the big supermarkets is quite effective and won't do any harm if used in the recommended doses, . . but make sure it's the stuff for diesel fuel systems and not the sort intended for the petrol fuel injection systems found on cars. Yes, I read up on it before putting some in. I decided to use it as a one off just to flush it really. 100ml into 100 litres of fuel. I've now got some forte additive for future use. I've managed to get glow plugs from Minnesota for the princely sum of 29 quid, so that's one issue sorted. I'll next find some injectors or get these refurbished.
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Post by Deleted on Jun 15, 2020 8:53:27 GMT
Thanks TonyDunkley Its good advice. I did wonder about the push rods. I'll get them out and have a good look, and set the clearances on the other unit. They are nice low hours engines so as you say worth looking after I expect push rods might be an easy to source part.
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