Nearly lost my engine today !!
Posted: Sat Feb 27, 2010 9:42 pm
I went over to Tricky's workshop today to have another fiddle with the Holley carb.
Last time I was at the pod, it would be a bugger to start, then idle with lots of black smoke and then clear. It was obvioulsy not firing on all 8. But after a minute at 1500rpm she wouild pick up and run. But then go rich again?
Today I had the velocity stack fitted with no gasket just to keep crud out while on the trailer.
The race tank was full with 1.5 gallons.
I turned the key and she fired, but then died after 2 seconds?
I gave a couple of pumps and tried again. Still no go.
This is where I was lucky. Tricky was under the bonnet while I was trying to start her. I left the ignition on (which means the fuel pump was running) while I was chatting to Tricky.
He then noticed petrol seeping out from the air filter?
I looked and could see petrol coming from all over the place.
I turned it off and could then hear what sounded like water trickling?
I took off the stack and turned the ign back on. A plume of petrol gushed upwards from the primary signal pipe as fast as I could pee??
I looked in the tank and it was half empty. 3/4 of a gallon had run into the inlet manifold!!
I took the plugs out and cranked it over. It was like a musical fountain display with petrol gushing from each plug hole
I squirted oil in each bore and cranked again for 10 seconds. Then more oil and cranked again until droplets stopped coming out. More oil and 2 hours to let it dry while I pulled the carb and found the float full of petrol?
Luckily Tricky had a spare 600dp so I nicked the float out of that.
I set the flaot height and started the engine. She was running rough as fook. We used the laser thermometer to find 1 and 8 were not running as hot as the others. I chucked a set of B8's in that tricky had and she ran smooth. So my C55 plugs have been compromised I think.
I was concerned about the amount of pretrol that may have got into the sump. Although when I smelt the dipstick it didnt smell of petrol?
So I let it idle to 80C and shut it off. She cooled to 30C while I was titting around with bolting the seat in and I started it again. This time I cranked it without pumping the pedal and she fired and idled after about 4 seconds of cranking. PHEW!!
I did a hot compression test and found that all was as before!
So here I was with the engine idling, no change to the carb settings or jets. Just a set of stock Rover plugs fitted. Now it was time to see if I could find the reason for the bog when going from idle to wide open throttle. I gave it a few revs and she responded really well on the primaries only. I then told Tricky that the problem was the flat spot as the secondaries flipped open. It was idling at 900rpm and I flipped the carb wide open. It didint hesitate. It just wizzed up to 6000 rpm in the blink of an eye? I repeated this 3 or 4 times with no problem?
So! Could the plugs be the problem? Maybe I should go back to the B8ECS ones I used before?
I'm off to the Pod tomorrow to do some more testing. If this thing will launch off gas without a bog I'll be very happy. If it does (and I'll find out in the pits) I might drop back to a 100 shot to see how things go. I dont think these plugs will take a 300 shot, so I'll have to take it easy
As I've only ever run Webers. I was dreading setting up the Holley. But after todays work, they aint that bad to work on eh?
Even trhough you have to drain the bowls. The jet changing is much easier than the Weber 500 I reckon.
So tomorrows first job at the pod is oil and filter change. Then have some practice launches in the pits to see if the bog has gone?
I really thought I could have washed the bores out today. But the old warhorse seems to live to fight another day
Last time I was at the pod, it would be a bugger to start, then idle with lots of black smoke and then clear. It was obvioulsy not firing on all 8. But after a minute at 1500rpm she wouild pick up and run. But then go rich again?
Today I had the velocity stack fitted with no gasket just to keep crud out while on the trailer.
The race tank was full with 1.5 gallons.
I turned the key and she fired, but then died after 2 seconds?
I gave a couple of pumps and tried again. Still no go.
This is where I was lucky. Tricky was under the bonnet while I was trying to start her. I left the ignition on (which means the fuel pump was running) while I was chatting to Tricky.
He then noticed petrol seeping out from the air filter?
I looked and could see petrol coming from all over the place.
I turned it off and could then hear what sounded like water trickling?
I took off the stack and turned the ign back on. A plume of petrol gushed upwards from the primary signal pipe as fast as I could pee??
I looked in the tank and it was half empty. 3/4 of a gallon had run into the inlet manifold!!
I took the plugs out and cranked it over. It was like a musical fountain display with petrol gushing from each plug hole
I squirted oil in each bore and cranked again for 10 seconds. Then more oil and cranked again until droplets stopped coming out. More oil and 2 hours to let it dry while I pulled the carb and found the float full of petrol?
Luckily Tricky had a spare 600dp so I nicked the float out of that.
I set the flaot height and started the engine. She was running rough as fook. We used the laser thermometer to find 1 and 8 were not running as hot as the others. I chucked a set of B8's in that tricky had and she ran smooth. So my C55 plugs have been compromised I think.
I was concerned about the amount of pretrol that may have got into the sump. Although when I smelt the dipstick it didnt smell of petrol?
So I let it idle to 80C and shut it off. She cooled to 30C while I was titting around with bolting the seat in and I started it again. This time I cranked it without pumping the pedal and she fired and idled after about 4 seconds of cranking. PHEW!!
I did a hot compression test and found that all was as before!
So here I was with the engine idling, no change to the carb settings or jets. Just a set of stock Rover plugs fitted. Now it was time to see if I could find the reason for the bog when going from idle to wide open throttle. I gave it a few revs and she responded really well on the primaries only. I then told Tricky that the problem was the flat spot as the secondaries flipped open. It was idling at 900rpm and I flipped the carb wide open. It didint hesitate. It just wizzed up to 6000 rpm in the blink of an eye? I repeated this 3 or 4 times with no problem?
So! Could the plugs be the problem? Maybe I should go back to the B8ECS ones I used before?
I'm off to the Pod tomorrow to do some more testing. If this thing will launch off gas without a bog I'll be very happy. If it does (and I'll find out in the pits) I might drop back to a 100 shot to see how things go. I dont think these plugs will take a 300 shot, so I'll have to take it easy
As I've only ever run Webers. I was dreading setting up the Holley. But after todays work, they aint that bad to work on eh?
Even trhough you have to drain the bowls. The jet changing is much easier than the Weber 500 I reckon.
So tomorrows first job at the pod is oil and filter change. Then have some practice launches in the pits to see if the bog has gone?
I really thought I could have washed the bores out today. But the old warhorse seems to live to fight another day