EFA Posted March 4, 2001 Share Posted March 4, 2001 Chaps and Chapesses..... Having changed from a crank driven hall effect ignition sensor to a flywheel driven variety, I seem to have hit a problem where my newely rebuilt engine refuses to run. Because the radius of the timing marks is greater I think I may have made an error calculating the position of the sensor. All cam timing etc. appears correct, fueling is working, and everything has been double checked. The ignition uses a wasted spark system so its not possible to set the spark on the wrong stroke. Attaching a timing light to cyl 1 however it seems at cranking rpm (230rpm) the igintion is firing at about 50 or 60 degrees before TDC. Quite what happens when it fires I do not know for it has only run for about 5 seconds total in the 2 days I've been trying to start it. The ECU is an MBE 912v3 and is not user programable so I cannot offset the advance on the sensor. Can anyone out there tell me if 50 to 60 degrees is acceptable advance at cranking rpm on a cold engine???? Arnie Webb The Fat Bloke blush.gif in a Knackered Old Vauxhall wink.gif Edited by - fast arnie on 4 Mar 2001 12:52:36 Link to comment Share on other sites More sharing options...
AMMO Posted March 4, 2001 Share Posted March 4, 2001 Arnie, not 100% sure that I'm not talking out of my bottom, but I would expect 10 degrees approx. at cranking speeds. 50 to 60 degrees you would only encounter on the over run on a closed throttle at high rpm. I used to run race engines on crank triggered ignitions locked up at 32 degrees and they were always abit of a struggle to start. I don't know how your box is triggered and what type of pickup you have but is it possible the flywheel (if it's flywheel triggered) is in the wrong position? Just clutching at straws Arnie. AMMO Link to comment Share on other sites More sharing options...
EFA Posted March 4, 2001 Author Share Posted March 4, 2001 Ammo The flywheel only bolts on in one position on a Vaux. I simplyt can't wprk out how it can be that far out if 10 degrees is the norm. Interestingly the ECU does have some read only software which shows 49 degree ign advance when the engine is stationary - I wonder if this corroborates the readings I am getting... Arnie Webb The Fat Bloke blush.gif in a Slow Old Vauxhall wink.gif Link to comment Share on other sites More sharing options...
AMMO Posted March 4, 2001 Share Posted March 4, 2001 Arnie, I've got a demo version of some MBE software (probably for Vauxhall as it came from a Vauxhall specialist) and sure enough the ignition has loads of advance at cranking speed. About 32 degrees. This then decreases to 0 degrees and works it's way up again. How does the flywheel trigger the pickup? How many teeth? Did you have to intall the pickup yourself or was there provision for it already. I had a problem with a Weber-Marelli system once which drove me nuts for a couple of days. Turned out that the pickup was to close to the flywheel. On the original flywheel 1 mm clearance was OK. I fitted a skimpy light flywheel and the bugger wouldn't start. I reduced the clearance thinking this would do the trick, still nothing. In the end I had someone crank the motor while I fiddled with the sensor. Increasing the distance did the trick. Once running I was suprised how far away from the flywheel I could pull the pickup. Might not be the problem but worth a try perhaps? AMMO Link to comment Share on other sites More sharing options...
EFA Posted March 4, 2001 Author Share Posted March 4, 2001 Definately worth a try..... - I set the gap to 1mm as on the original gap between the sensor and the crank..... Have checked the spark though and its very definate at around 50 deg btdc. This is really weird.... How much further away did you move the sensor in your case?? Were the teeth a different shape or size on the new flywheel???? Arnie Webb The Fat Bloke blush.gif in a Slow Old Vauxhall wink.gif Link to comment Share on other sites More sharing options...
AMMO Posted March 4, 2001 Share Posted March 4, 2001 Arnie, all this happened about four years ago. I tried reducing the gap to .8mm but eventually ended up with 1.5 mm. The flywheel had the same amount of teeth (4 only, it also had a cam sensor for a sequential injection system) but the mass of the flywheel was greatly reduced. This was the only change made. Never could get anyone to explain what was going on. All I know is that it worked (and is still working like that to this day). AMMO Link to comment Share on other sites More sharing options...
Paul D Jones Posted March 4, 2001 Share Posted March 4, 2001 Is it possiable to get the flywheel in the wrong position I know it is not possiable on a Zetec 5 bolt and an offset PCD.If it is a 6 bolt PCD and one pitch out it would be 60 degs wrong. Its an engine out to check so maybe someone knows better than me can say for sure. Link to comment Share on other sites More sharing options...
CHRIS CLARK Posted March 4, 2001 Share Posted March 4, 2001 Commiserations Arnie; frustrating or what! I have to say these ECU's are the bit I 'fear' most!!! Good Luckthumbsup.gif Link to comment Share on other sites More sharing options...
EFA Posted March 4, 2001 Author Share Posted March 4, 2001 Paul, The VX flywheel only bolts on in one position. The 49deg btdc cold start could be very borderline, and my guestimate of sensor position could be +/- 6 degrees. It may just have advanced it too much. Interestingly, removal of the temp sensor sets a default temp of 90 deg c, and a crank timing of 19.9deg btdc - weird that it is, no change is evident at the timing light! Guess I need to buy an MBE 956 ECU which is user programable and go from there. So two things: 1. Another £500 has just bitten the dust, 2. Where is Peter C when I need a scientific explanation..... Arnie Webb The Fat Bloke blush.gif in a Slow Old Vauxhall wink.gif Edited by - fast arnie on 4 Mar 2001 21:14:19 Link to comment Share on other sites More sharing options...
Mike Bees Posted March 5, 2001 Share Posted March 5, 2001 AMMO's right Arnie, you'd expect to see around 10 degrees of advance at cranking speeds, and would only see anything like as much as 50 degrees on the overrun (wind this down for extra popping effects). Mike Link to comment Share on other sites More sharing options...
Roger King Posted March 5, 2001 Share Posted March 5, 2001 Yup, Mike and Ammo are correct. 10 degrees (maybe up to 15 degrees at a push) would be a reasonable figure. There is no way you'll start with a figure of 50 degrees. I guess it kicks back like a mule. Link to comment Share on other sites More sharing options...
EFA Posted March 5, 2001 Author Share Posted March 5, 2001 Thx Mike Roger and Ammo, I agree - for a very high compression ratio I have been advised it may go to 25 degrees but absolutely no more...... My engine runs 11.7:1 So to fix things I need to set the pickup offset to compensate, meaning new (non eprom based)ECU. Which to buy is a major dilemma. DTA - DTA will at least send me a new plug to solder on the end of my exisiting MBE loom - not too difficult, I made the exisiting loom myself. Engine would however need remapping. Emerald - It looks very cheaply made - folded ali casing - is it watertight??? Also I would need to integarte a new loom (making injector cuts for my Racelotic Traction control) and the engine would need remapping. MBE - 1 956 would be plug compatible with my existing loom, 967 (a la R500) is cheaper. Could also convert existing map to run on a 956, although the 956 only supports the Easimap utility up to version 4 - apparently not so user friendly - anyone have any experience with Easimap??? May require a rolling road session to reset timing datum point. GEMS ??????? Any others anybody can think of???? Any info on the pitfalls or strong points of any of thge above greatly received. The only fixed criteria are that it must be as small or smaller than the DTA...... Arnie Webb The Fat Bloke blush.gif in a Slow Old Vauxhall wink.gif Link to comment Share on other sites More sharing options...
Mike Bees Posted March 6, 2001 Share Posted March 6, 2001 If you're planning on further engine mods (can't be very much more you can do to it) in the near future then surely the easiest option is the MBE 956 - no remapping, no loom changes. Surely it must be possible to convert a 956 map to a 967? OTOH if you have your map in some sort of human-readable form then it should be possible to convert it for a DTA or Emerald box. The DTA has traction & launch control built in, Emerald will have it in the version they're currently working on. Don't know whether they do or will work as well as the Racelogic though. I was under the impression that higher compression engines ran less advance at cranking speed to reduce/avoid kickback - have I got this wrong? Mike Link to comment Share on other sites More sharing options...
Peter Carmichael Posted March 6, 2001 Share Posted March 6, 2001 My engine cranks with 5 degrees advance and starts very well. When starting it for the first time I thought a bit of air might help it so I opened the throttle butterflies slightly using the stop. Had to ring Dave Andrews and seek advice when it wouldn't fire. He told me to close the butterflies, crank until it fired and then give it a gulp of air - fired first time. Because of the slow cranking speed, a small butterfly opening translates into an almost completely full cylinder and then it becomes quite a task to get the mixture to fire - or something like that. The mapped idle is set on an abrupt ramp from 25 degrees at 500rpm down to 6 degrees at 1000rpm. The ECU controls the advance below 1500rpm with a closed throttle up to a maximum of 25 degrees and aiming at an idle of 1100rpm. The idle fuelling is set on a gentle ramp from 2.62ms at 500rpm down to 2.44ms at 1000rpm and then 1.28ms@1500 rpm (I know the numbers won't translate directly, but the shape of the ramp is the important bit). This gives a rock steady idle. A more abrupt fuelling ramp results in the engine hunting for an idle. Edited by - Peter Carmichael on 6 Mar 2001 08:51:49 Link to comment Share on other sites More sharing options...
EFA Posted March 7, 2001 Author Share Posted March 7, 2001 Well today i put some 8v std 1.8 Vauxhall branded super hot running cheepo plugs in and it ran. ish. It would only run if I pulled the temp sender off so the ECU went to the default 90 deg. With the sender connected it wouldn't even try to go. Tons of crap came out of the exhaust, it appears to be running richer than I let it run for about 2 mins, but it would stall if I let it run below 2500rpm, and when I blipped the throttle it sounded very off pitch (not misfiring, but like it was only running on 3 cyls. Lack of harsh vibration and 4 hot primaries leads me to conclude it was running on all 4. If I was over liberal with the oil during the build of the engine how long would this take to clear - the noise is rather anti social to say the least - don't want to end up doing a PC...... So question to the experts is could this still be an over advance issue or is it something else?? What would you do?? Arnie Webb The Fat Bloke blush.gif in a Slow Old Vauxhall wink.gif Link to comment Share on other sites More sharing options...
Alex Wong1697456877 Posted March 7, 2001 Share Posted March 7, 2001 I once had an ecu to loom connection problem where all the senders weren't getting to the ecu (apart from crank position I think). The get you home settings made it very rich and itmade horrendous noises. I doubt your problem is this simple though... Cheers, Alex Edited by - Alex Wong on 7 Mar 2001 23:06:43 Link to comment Share on other sites More sharing options...
Mike Bees Posted March 8, 2001 Share Posted March 8, 2001 Have you looked at the plugs Arnie? It sounds as though it's horrendously rich (witness it not being interested if it sees a low coolant temp). Are you sure the fuel pressure hasn't changed? Have you had a timing light on it while it's running to see what the advance is? Mike Link to comment Share on other sites More sharing options...
EFA Posted March 8, 2001 Author Share Posted March 8, 2001 The problem has been identified. My old machined crank appears not to actually be the old one machined, and is actually a different crank. No wonder the journals looked so good, I thought they had polished them. The new crank has a 45 degree offset in the flywheel mountings hence the timing is 45 degrees out. Is this the end of my problem? No. Guess who has an ecu which cannot have the timing sensor retarded far enough?? Me. So options are: Remove engine, ditch flywheel, get a new one and cut off the two teeth in a position appropiate to the new crank = loads of hard messy work. or Get a new ECU which can have a crank sensor offset outside the limited range of the 912v3 entered. Luckily the 956 from MBE will do this and is plug compatible with my loom. Trouble is it costs £580 so I hope the wife doesn't read this. Guess I'm going with option 2. Consequently my old ECU is for sale and it will work perfectly with a Vauxhall engine which retains the std crank flywheel mounts. I have maps for a Caterham 235 and a SBD 208 version of the Vx engine (this is just a Vaux with Jenvery throttle bodies) so if you are looking to go TB's on a VX on the cheap this is a good opportunity. So R500's watch out - This is Arnie saying "I'll be back" Arnie Webb The Fat Bloke blush.gif in a Slow Old Vauxhall wink.gif Link to comment Share on other sites More sharing options...
AMMO Posted March 8, 2001 Share Posted March 8, 2001 Arnie, just a thought. Why don't you forget about the flywheel and get a toothed disc to fit on the front of the crank pulley (if there's room). You can make a bracket to take the pickup and put both the disc and pickup in any position you like. This would resolve you're timing problem without taking the engine out. The bits may have to be made and would involve a bit of messing around, but still cheaper than buying a new ECU. I've seen a few engines that run like this. I asked you in a previous posting how many teeth you trigger had because it's possible to get trigger wheels from production cars very cheaply. I've been told £10 for a Ford 36 minus 2 (or minus 1, can't remember)wheel. Hope this makes sense. It's been a long day. Troppo Vino Rosso AMMO Link to comment Share on other sites More sharing options...
AMMO Posted March 8, 2001 Share Posted March 8, 2001 Arnie, another thought. ECU manufacturers can either supply trigger wheels or point you in the direction of engineering companies who make them. AMMO Link to comment Share on other sites More sharing options...
EFA Posted March 8, 2001 Author Share Posted March 8, 2001 Ammo, Theres little room at the front of the engine, and the risk of damage when inserting/removing the engine is high.... ECU I think is the best option, and I can raise the redline to 10,000rpm when Mr Krebs is around..... Arnie Webb The Fat Bloke blush.gif in a Slow Old Vauxhall wink.gif Link to comment Share on other sites More sharing options...
Jason Posted March 8, 2001 Share Posted March 8, 2001 Hi Arnie I've been in Germany for a couple of days (work not at the Ring getting practice for our duel) so your R500 part is on it's way in the morning. Please don't raise your rev's to 10,000 when I'm next to you I don't want my car covered in oil and bit's of your block smile.gif. I at last got my engine back from Ministers today smile.gif Good luck Jason R500FUN PS my MBE will be for sale shortly if you want more R500 parts Link to comment Share on other sites More sharing options...
EFA Posted March 9, 2001 Author Share Posted March 9, 2001 Jason When I spoke to Minister (They are an MBE dealer) they told me they had no problem getting 250 horse from a K. So I think you may be telling a porky pie?????? Arnie Webb The Fat Bloke blush.gif in a Slow Old Vauxhall wink.gif Link to comment Share on other sites More sharing options...
metal mickey Posted March 9, 2001 Share Posted March 9, 2001 Arnie, Thank god youv'e got the problem sorted before Le mans, I thought you'd want a lift. My mates got a spare seat in his W-------d if you have any more problems. slowly retreating now to put flak jacket on. Link to comment Share on other sites More sharing options...
Jason Posted March 9, 2001 Share Posted March 9, 2001 Arnie Up until 10 day's ago this was believed to be the case but upon running the test engine on the dino David Minister was not happy (wouldn't say any more as to why) so no 250 at this time but sometime soon hopefully. Jason PS your part was posted today Link to comment Share on other sites More sharing options...
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