Bowie69 Posted May 25, 2013 Share Posted May 25, 2013 Normally I'd use something like blue hylomar for sealing up the plenum/trumpet, RTV if it has silicon in it kills lambdas, so I avoided it at all costs when building the inlet tract to mine. Quote Link to comment Share on other sites More sharing options...
Hybrid_From_Hell Posted May 25, 2013 Share Posted May 25, 2013 MT > Basic Setting >EGO correction Set all cells after top to 0 save Quote Link to comment Share on other sites More sharing options...
mikec Posted May 25, 2013 Author Share Posted May 25, 2013 Normally I'd use something like blue hylomar for sealing up the plenum/trumpet, RTV if it has silicon in it kills lambdas, so I avoided it at all costs when building the inlet tract to mine. Wasn't aware of that, although I have read recently about silicone attacking metals. I used wurth instant gasket. Quote Link to comment Share on other sites More sharing options...
mikec Posted May 25, 2013 Author Share Posted May 25, 2013 With those 4 cells on the ve set to 50 I get 835-944. I realise its only a bodge but least I can play a bit this weekend Quote Link to comment Share on other sites More sharing options...
Bowie69 Posted May 25, 2013 Share Posted May 25, 2013 Wasn't aware of that, although I have read recently about silicone attacking metals. I used wurth instant gasket. If you check the packet, it may say 'sensor safe' in which case it is OK, but I haven't found a Wurth instant gasket that doesn't contain silicon, at least from a quick google. Quote Link to comment Share on other sites More sharing options...
Hybrid_From_Hell Posted May 25, 2013 Share Posted May 25, 2013 With those 4 cells on the ve set to 50 I get 835-944. I realise its only a bodge but least I can play a bit this weekend Thats much better - NOW connect up the PWM ??????? Nige Quote Link to comment Share on other sites More sharing options...
Bowie69 Posted May 25, 2013 Share Posted May 25, 2013 Needs to set base idle first really... otherwise at idle the valve will be shut. Quote Link to comment Share on other sites More sharing options...
mikec Posted May 25, 2013 Author Share Posted May 25, 2013 Well I've had a nit of a play both off road and with the Megasquirt/engine. Tried the hand over the inlet again, it stops but first thing I noticed it sucks air in thought the tiny breather on the rocker cover. That's probably normal? But when I covered that breather hole over I could still hear a hissing/sucking, so there's still a bit of at leak somewhere, but it must be small say half the size of that small breather diameter. Is that small a leak going to cause such problems? Quote Link to comment Share on other sites More sharing options...
Hybrid_From_Hell Posted May 26, 2013 Share Posted May 26, 2013 Yes .! Quote Link to comment Share on other sites More sharing options...
FridgeFreezer Posted May 27, 2013 Share Posted May 27, 2013 Just to pick up a couple of things (I don't have the mental fortitude to read the entire saga!): - An air leak can throw things off in odd ways, especially if it's on one bank or one cylinder, as one may then run lean and the rest will get richened more than it needs, because the lambda sensor only sees the "average" of what flies down the exhaust. - A different fuel map may well mask a problem or make it much worse depending, a bit like a lump of mud in your wheel rim could help balance the wheel or make it wobble like a whassname. - An engine can idle on almost no air (see the closed butterfly & the very small idle air channel needed to keep a V8 ticking over!) and therefore a pinhole leak can easily make a significant difference. - Change one thing at a time, and stay cool. Quote Link to comment Share on other sites More sharing options...
mikec Posted June 2, 2013 Author Share Posted June 2, 2013 Finally got round to doing something about this today, so cut up an old inner tube and jubilee clipped it to the intake, then pumped air into it, squirted everything around the intake with soapy water, found a few small leaks, one around one of the pwm plate bolts on the back of the plenum, one on the throttle spindle into the plenum and one on the idle adjusting screw. I can also hear a hissing which sounds like its coming from under the intake somewhere but can't find it yet. Last weekend a whistling sound also appeared bit like turbo whistle on an hgv!! Only a certain load/revs, guessing its the same leak, just gotta find the blooming thing. Unfortunately my airline burst so can't investigate further till I get that sorted Quote Link to comment Share on other sites More sharing options...
Chazza Posted June 3, 2013 Share Posted June 3, 2013 Well done Mike; the pressure test is a very good idea! Pardon me mentioning it, but with so many air leaks, I wonder about your attention to detail when you assembled it. 1. Inspect closely every face for burrs, or lumps, which can usually be lightly draw-filed with a 6" smooth file to get them flat again; or a longer file for larger surfaces. 2. Make sure every piece of old gasket is removed completely. I use an old power-hacksaw blade to gently scrape the stubborn ones off. 3. Clean all mating surfaces with Prepsol, or something similar, before assembly. 4. If you use a liquid gasket use it sparingly and make sure before putting it on, that it is suitable for the task. For paper gaskets Loctite 515 is a suitable dressing - if required - for most applications. 5. Do not re-use old gaskets; seals and O-rings if you can avoid it. 6. A thin film of Loctite 515 inside the ends of hoses, not only leak-proofs them, but on cooling systems, seems to stop the metal from corroding. 7. Cleanliness, cleanliness; cleanliness! Cheers Charlie Quote Link to comment Share on other sites More sharing options...
mikec Posted June 3, 2013 Author Share Posted June 3, 2013 Well done Mike; the pressure test is a very good idea!Pardon me mentioning it, but with so many air leaks, I wonder about your attention to detail when you assembled it. 1. Inspect closely every face for burrs, or lumps, which can usually be lightly draw-filed with a 6" smooth file to get them flat again; or a longer file for larger surfaces. 2. Make sure every piece of old gasket is removed completely. I use an old power-hacksaw blade to gently scrape the stubborn ones off. 3. Clean all mating surfaces with Prepsol, or something similar, before assembly. 4. If you use a liquid gasket use it sparingly and make sure before putting it on, that it is suitable for the task. For paper gaskets Loctite 515 is a suitable dressing - if required - for most applications. 5. Do not re-use old gaskets; seals and O-rings if you can avoid it. 6. A thin film of Loctite 515 inside the ends of hoses, not only leak-proofs them, but on cooling systems, seems to stop the metal from corroding. 7. Cleanliness, cleanliness; cleanliness! Cheers Charlie The only leak I've had so far (that ive found!) that was down to me is the pwm "plate" things like leaking idle screw and throttle spindle I've not touched. Quote Link to comment Share on other sites More sharing options...
mikec Posted June 3, 2013 Author Share Posted June 3, 2013 Another go with this bloody thing tonight, finished off swapping plenums to try and fix some of the leaks above. The noise from above is still there. Thought I'd start it up and see what it ran like, just on the off chance, anyway it idled a ok so thought I'd give it a few blips to see if the flatspot had gone, it was loads better felt "different" too. Then I realised the map pipe was still off, shoved that back on and it was the same as before. Not sure what else to try now, cant for the life of me find this noise/leak/whatever it is. So looks like ill have to bite the bullet and try and find a garage to look at it. Quote Link to comment Share on other sites More sharing options...
FridgeFreezer Posted June 4, 2013 Share Posted June 4, 2013 If it ran much better with the MAP pipe off it would/should have been running dog rich & lumpy. As an experiment, start it up and then increase the REQ_FUEL value by, say, 25% to see if that makes it behave better. If it doesn't knacker it, try adding another 25% and see what happens. If you have air leaks & have been tuning to the lambda (oxygen) sensor reading you can end up off in the weeds as surplus air leaking in gives false "rich" readings (as air contains more oxygen than exhaust gas), this can steer the tuning far too lean as it attempts to compensate for the false reading. DO NOT SAVE the REQ_FUEL changes, it's just an experiment! Quote Link to comment Share on other sites More sharing options...
mikec Posted June 4, 2013 Author Share Posted June 4, 2013 If it ran much better with the MAP pipe off it would/should have been running dog rich & lumpy.As an experiment, start it up and then increase the REQ_FUEL value by, say, 25% to see if that makes it behave better. If it doesn't knacker it, try adding another 25% and see what happens. If you have air leaks & have been tuning to the lambda (oxygen) sensor reading you can end up off in the weeds as surplus air leaking in gives false "rich" readings (as air contains more oxygen than exhaust gas), this can steer the tuning far too lean as it attempts to compensate for the false reading. DO NOT SAVE the REQ_FUEL changes, it's just an experiment! I'm just running niges supplied map with ego turned off. Ill give it a go but don't wanna knacker anything. I'm wondering wether to see if Roland at acr would look at it he built the block and heads up and seemed sound enough. Think it just needs a second pair of ears on it as I don't think I'm getting anywhere. Quote Link to comment Share on other sites More sharing options...
FridgeFreezer Posted June 4, 2013 Share Posted June 4, 2013 It does sound like you need a 2nd set of eyes on it, familiar with RV8's. Can you not tempt Nige over to have a look? Quote Link to comment Share on other sites More sharing options...
mikec Posted June 4, 2013 Author Share Posted June 4, 2013 It does sound like you need a 2nd set of eyes on it, familiar with RV8's. Can you not tempt Nige over to have a look? Haha I wish, it's a bit far from Surrey to Manchester Half the problem is that the engine was never run as it is now, it was fitted with a Thor inlet etc. so it could literally be anything, rather than normally saying such and such was working. I'm just debating wether to go have another bash at it tonight, thing is I get wound up when it doesn't go to plan Quote Link to comment Share on other sites More sharing options...
Bojerne Posted June 4, 2013 Share Posted June 4, 2013 Have you checked the stepper/IAC is fully closing - the howling could be due to a faulty stepper motor - or it's just not fully closing ? Have a nice day Michael Quote Link to comment Share on other sites More sharing options...
FridgeFreezer Posted June 4, 2013 Share Posted June 4, 2013 Ah, what with you not filling in your location it was hard to tell Getting frustrated is guaranteed to lead to problems, missing small things, etc. - best thing is to walk away, have a cuppa, think about something else and come back with a clear head. The problem is it's so easy to get used to your truck being a certain way, and someone else will stick their head under the bonnet and go ""Why is that pipe like that?", even though you've looked at it 100 times and not seen it. Quote Link to comment Share on other sites More sharing options...
mikec Posted June 4, 2013 Author Share Posted June 4, 2013 Haha that what I'm expecting/hoping. I put a post on the ms forum to see if someone was local, but didn't get anywhere. Quote Link to comment Share on other sites More sharing options...
mikec Posted June 4, 2013 Author Share Posted June 4, 2013 Have you checked the stepper/IAC is fully closing - the howling could be due to a faulty stepper motor - or it's just not fully closing ?Have a nice day Michael Sorry missed that post, it has no stepper, just using pwm but blanked off/disconnected ches mike Quote Link to comment Share on other sites More sharing options...
mikec Posted June 5, 2013 Author Share Posted June 5, 2013 Another hour on it tonight, I'm gonna replace the spindle seal, not sure if its worthwhile but if it does cure that leak it may make finding any others easier, although I'm not convinced its a real problem as both plenums have leaked there so I imagine its common on most of them. I keep wondering about where the injectors mount into the manifold, but the soap doesn't show anything there. Other than that I can only think to try swapping the inlet manifold just incase its warped or something? Not sure if that's likely or not. Quote Link to comment Share on other sites More sharing options...
Mr Noisy Posted June 5, 2013 Share Posted June 5, 2013 Haha that what I'm expecting/hoping. I put a post on the ms forum to see if someone was local, but didn't get anywhere. Am I not allowed to help? Quote Link to comment Share on other sites More sharing options...
Hybrid_From_Hell Posted June 5, 2013 Share Posted June 5, 2013 wtf is a spindal seal ?? Quote Link to comment Share on other sites More sharing options...
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