Fuel starvation when maxing out? |
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Fuel starvation when maxing out? |
David Stowers |
Feb 10 2014, 07:01 AM
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#1
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Member Group: Members Posts: 99 Joined: 28-June 12 From: UK Member No.: 14,613 Region Association: None |
My 914 is running a 1.8 (ish!) 40 Dellortos and recently recorded 111BHP and 121lbft of torque after a carb set up so yesterday I went to have a little thrash about.
A couple of times when the traffic cleared I really kept my foot flat down and pushed to over 100MPH on a slight uphill. It was still pulling strongly for a few seconds then seemed to lose power and splutter slightly. I backed off and it returned to normal. It seemed like the carbs emptied as if the fuel pump couldn't keep up. I had the heater on and the rich oily aroma changed to a hot sharp smell like it suddenly ran lean. It's running the small square facet pump mounted up front near the master cylinder. Any ideas please Thanks David |
David Stowers |
Apr 13 2014, 03:08 PM
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#2
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Member Group: Members Posts: 99 Joined: 28-June 12 From: UK Member No.: 14,613 Region Association: None |
OK, so just incase anyone remembers or cares I was having what seemed to present as a fuel starvation issue.
Last week I took the still unwell car to an airfield track day despite knowing I should solve the problem first. Well you guessed it, I broke it (IMG:http://www.914world.com/bbs2/uploads_offsite/i595.photobucket.com-14613-1397423305.1.jpg) Despite the complete meltdown of the plug after much head scratching and beard stroking I borrowed a spare plug and with eyes closed turned the key. It didn't run too badly so I thought we could make it a couple of miles from the track and call the recovery truck. It made it 130 miles all the way home!! The following day I drooped the engine and removed he damaged head. The offending plug port had a helicoil insert and now a fair bit of damage to the seat face. I had a pair of spare heads so had one cleaned and the valves reground. Yesterday I fitted it and re installed the engine. You're ahead of me, the issue I had is gone (IMG:style_emoticons/default/cheer.gif) (IMG:style_emoticons/default/cheer.gif) (IMG:style_emoticons/default/cheer.gif) I can only assume the insert was bad or the fitting of it had cracked the head and when under load for a prolonged period the crack would open with the heat and cause the spluttering as if fuel had run out. By backing off the fuel supply wasn't catching up as I thought but the head was cooling sufficiently to close the crack or leak past the insert. I've spent best part of £1000 and numerous hours trying to solve this when all I needed to do was break it a bit more! Thanks all for your input, I've learnt a lot. |
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