disco-v8 Posted November 5, 2007 Share Posted November 5, 2007 ok im still having problems with my V8, and ive chequed alot of the electrics and all seems ok so far, i also found a problem with the dizzy (had abit of water inside ) so now its running better but not 100% and im still getting popping through the air box!!!!! its time to start to take things apart now to see if its something mechanicle... i realy want to see if the cam is timed up correctly, i tryed to work it out through the oil filler cap but the cam that i have must have a flat apex on it as the exhaust valve stays at its peek for atleast 8 degrees so i cant find the exsact point of where its fully closed so i cant tell if its timmed up properly..... i started to take parts off and got to the plenum chamber when i found out this happened... god nos why i started it but kinder glad i did.... i know the fueling is going to be messed up as it hasnt got the stepper motor plugged in, the air flow meter, the potentionmeter, and the trummpets are fully open....... BUT IS THIS REALY MENT TO HAPPEN??????? http://uk.youtube.com/watch?v=4nhfG6nB37c Quote Link to comment Share on other sites More sharing options...
FridgeFreezer Posted November 5, 2007 Share Posted November 5, 2007 Erm, exsqueeze me? What exactly are you expecting to happen when half the ECU's inputs are missing and you have done the equivalent of putting a brick on the accelerator? Lucky it didn't catch and rev itself to pieces. ...make the suspension adjustable and they will adjust it wrong -- look what they can do to a Weber carburetor in just a few moments of stupidity with a screwdriver.Colin Chapman Quote Link to comment Share on other sites More sharing options...
disco-v8 Posted November 5, 2007 Author Share Posted November 5, 2007 Erm, exsqueeze me? What exactly are you expecting to happen when half the ECU's inputs are missing and you have done the equivalent of putting a brick on the accelerator? Lucky it didn't catch and rev itself to pieces. yes we all no that it doesnt make sence why i started it and i still dont no why i started, but thats not the point, im sure its not ment to do this even with all the imputs missing....... and it had no chance of revving its self to death, that why i stood there with my hand on the ignition keys except for the butter fly valve on the throttle been missing i cant see there been to much of a problem, ive ran my engine while the air flow meter has been off before to see if that was a fault, and ive ran it with out the potentionmeter on aswell...... its still getting fuel from the injectors (fare enough it might be to much fuel) and its got the correct ignition timing so its got a spark..... its like a poorly running carb engine but i dont see them spitting flames out the carb!!!!!! Quote Link to comment Share on other sites More sharing options...
BogMonster Posted November 5, 2007 Share Posted November 5, 2007 ...make the suspension adjustable and they will adjust it wrong -- look what they can do to a Weber carburetor in just a few moments of stupidity with a screwdriver.Colin Chapman :hysterical: :hysterical: :hysterical: Quote Link to comment Share on other sites More sharing options...
FridgeFreezer Posted November 5, 2007 Share Posted November 5, 2007 i cant see there been to much of a problem That may be your problem Since you say (in your other thread) it was running fine till it got muddy I can't believe something like the cam timing has suddenly "gone wrong" Quote Link to comment Share on other sites More sharing options...
Bull Bar Cowboy Posted November 5, 2007 Share Posted November 5, 2007 With the plenum off there will be on induction vacuum, and although the engine will start, it would run very, very lean ……………and spit back through the inlet ......... which is what you are seeing ................. What exactly are you trying to check by looking at the exhaust rocker moving ? ………………. Once the cam lobe has opened the valve, there will appear to be a few degreees of ‘nothing’, however, if you were to place a dial gauge on the lifter, it would clearly show a well defined lift, peak and fall …………… You cannot really check the cam easily as it has hydraulic lifters and these are only fully primed when the engine is running ………….. a good check is to remove the inlet manifold & valley gasket, then you can clearly see the cam lobes and their general condition. …………….. if your engine has done 80K to 100K (ish ) then you can safely say that the cam is past its best (read totally knackered)…….......also the timing chain (if OEM) will be severely stretched and the rockers / rocker shafts will also show heavy wear …………. Ian Quote Link to comment Share on other sites More sharing options...
disco-v8 Posted November 6, 2007 Author Share Posted November 6, 2007 With the plenum off there will be on induction vacuum, and although the engine will start, it would run very, very lean ……………and spit back through the inlet ......... which is what you are seeing .................What exactly are you trying to check by looking at the exhaust rocker moving ? ………………. Once the cam lobe has opened the valve, there will appear to be a few degreees of ‘nothing’, however, if you were to place a dial gauge on the lifter, it would clearly show a well defined lift, peak and fall …………… You cannot really check the cam easily as it has hydraulic lifters and these are only fully primed when the engine is running ………….. a good check is to remove the inlet manifold & valley gasket, then you can clearly see the cam lobes and their general condition. …………….. if your engine has done 80K to 100K (ish ) then you can safely say that the cam is past its best (read totally knackered)…….......also the timing chain (if OEM) will be severely stretched and the rockers / rocker shafts will also show heavy wear …………. about 1000 miles ago i totaly reconed the engine and the cam, lifts and timing gear/chain where all changed at the time..... i didnt buy a standard cam i bought a piper RP4 cam which is designed for the 3.9 EFI autos..... the cam is stated at 18/62 62/18 with a vavle open duration of 270 degrees.... and as i could only see the exhaust valve through the oil filler cap i was cheacking to see if the valve was fully closed at 18 degrees BTDC (people who no anything about cams will understand this) basicaly im just trying to eliminate everything to my bad running and popping through the air box problem Ian Quote Link to comment Share on other sites More sharing options...
Hybrid_From_Hell Posted November 6, 2007 Share Posted November 6, 2007 Right V8s can be complex, if you have a problem with one there are a number of people on this forum who know a thing or 3 and would be worth tapping into. You have a Hotwire system, so my suggestion is you get a copy from the tech forum of the diagnostic guide I posted in there, this gives a step by step process of checking and working through the system in a logical and proven manner, I have lost count as to how many times this does the trick. Similarly Cap Rotorarm leads all need to be genuine, plugs NGK, again the number of "But they are good n new" comments that then later are proven to be the issue are huge... Taking bits off and apart here and there and then saying "why does it do this" is highly unlikley to get you anywhere, with a steel timing chain forget the timing "Jumping" its not a squeezallely diesel after all. Get the manual, check the above and report back Nige Quote Link to comment Share on other sites More sharing options...
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