Starting my engine on a stand, issues arose |
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Starting my engine on a stand, issues arose |
malcolm2 |
Sep 29 2020, 06:16 AM
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#41
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Advanced Member Group: Members Posts: 2,747 Joined: 31-May 11 From: Nashville Member No.: 13,139 Region Association: South East States |
I have built a fresh 2.0 and borrowed a set of weber 40s to get her running, broken-in etc....
I bought a new single vacuum distributor with the flame thrower 3 module inside. Also bought the Petronix coil. I built up oil pressure, then connected the gas lines, fuel pump, and coil. Tach and timing light too. After a few tries, she started. As expected running very ruff. Back-firing thru the carbs. I loosened the distributor and tried to make some adjustments. That seemed to help the back-firing a bit, but not totally. I got the idle timing to what looks like 7 btdc, but it is tuff to work everything without a helper. I know next to nothing about these carbs, and about the same amount to tune them enough to bench run the engine, but I am looking into that. Any help would be appreciated on the carbs. I got it idling, again, very ruff. So I wanted to do the cam break in, so I rev'd it up to about 3000 and held there. Maybe a minute and the revs dropped and I had to putz with the accelerator to keep her going. Again up to 3000, same thing revs dropped. I have a note in to my distributor vendor about how this "rev limiter" on this module works. So three things here. She is still running ruff, back-firing etc...and there is the high rev cut-off. Lastly the carbs, any quick checks or adjustments there? Any thoughts or suggestions? |
thelogo |
Sep 29 2020, 03:39 PM
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#42
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Senior Member Group: Retired Members Posts: 1,510 Joined: 6-April 10 Member No.: 11,572 Region Association: None |
Sorry but to encourage this is irresponsible
Theres a reason you should use a porsche mechinic (with the right tool's) for this kinda thing . unless you dont care if you accidentally melt down your engine prematurely. ( which you could very easily the way youre goin) Then go ahead. (IMG:style_emoticons/default/sheeplove.gif) Reminds me of my step dad who pryed the heads and intake off his cobra replica . so he could go for big power. The old heads and carb made way more power as they were dialed in . then the new stuff. Which he didnt know how to tune and could never get dialed in properly. Car just sits now. Weeping fuel . (IMG:style_emoticons/default/headbang.gif) Im no mechanic beyond oil changes. But i have a sobering sense of my limitations !!! |
Superhawk996 |
Sep 29 2020, 04:58 PM
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#43
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914 Guru Group: Members Posts: 5,903 Joined: 25-August 18 From: Woods of N. Idaho Member No.: 22,428 Region Association: Galt's Gulch |
Sorry but to encourage this is irresponsible Your overall point is valid. But, at this point he's comitted and has already spun it over to build oil pressure and it runs rough that much we know. At the beginning we all start somewhere. Hopefully on lawnmower, go carts, 2 stroke dirt bikes . . . whatever . . . that are less costly to fix if need be. Are there risks? Yes, but they are limited. I rebuilt my 1st teener engine at 22. It's not rocket science. Tom Wilson book clearly lays out what needs to be done. If one can follow a detailed recipe and have a sense of self imposed quality control, it is pretty easily done. Luckily, I started with a fresh new set of Webers and guidance from someone in the know to guide me. It was a 1.7L converted to 1911 and it all turned out great! Engine won't melt down on a test stand with no load unless it's being run at WOT for extended period and running lean and/or detonating. Seems OP at least realized something is wrong stopped to investigate. That is the correct thing to do. Previous post by Mark Henry is a sound plan of action and clearly outlines the preconditions that need to be addressed before trying to run it again. |
thelogo |
Sep 29 2020, 07:49 PM
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#44
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Senior Member Group: Retired Members Posts: 1,510 Joined: 6-April 10 Member No.: 11,572 Region Association: None |
Sorry but to encourage this is irresponsible Your overall point is valid. But, at this point he's comitted and has already spun it over to build oil pressure and it runs rough that much we know. At the beginning we all start somewhere. Hopefully on lawnmower, go carts, 2 stroke dirt bikes . . . whatever . . . that are less costly to fix if need be. Are there risks? Yes, but they are limited. I rebuilt my 1st teener engine at 22. It's not rocket science. Tom Wilson book clearly lays out what needs to be done. If one can follow a detailed recipe and have a sense of self imposed quality control, it is pretty easily done. Luckily, I started with a fresh new set of Webers and guidance from someone in the know to guide me. It was a 1.7L converted to 1911 and it all turned out great! Engine won't melt down on a test stand with no load unless it's being run at WOT for extended period and running lean and/or detonating. Seems OP at least realized something is wrong stopped to investigate. That is the correct thing to do. Previous post by Mark Henry is a sound plan of action and clearly outlines the preconditions that need to be addressed before trying to run it again. I just hate to see this guy end up like the other guy who had too build his second $$$$$ big /4 because a rod bearing was not secure and melted the thing down .the 1st time around. Dont learn on a type 4 build a few dozen stock 1600s And then tweak your teener engine. Its way cheaper to get a experienced person then to screw it up |
malcolm2 |
Sep 29 2020, 08:01 PM
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#45
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Advanced Member Group: Members Posts: 2,747 Joined: 31-May 11 From: Nashville Member No.: 13,139 Region Association: South East States |
Sorry but to encourage this is irresponsible Your overall point is valid. But, at this point he's comitted and has already spun it over to build oil pressure and it runs rough that much we know. At the beginning we all start somewhere. Hopefully on lawnmower, go carts, 2 stroke dirt bikes . . . whatever . . . that are less costly to fix if need be. Are there risks? Yes, but they are limited. I rebuilt my 1st teener engine at 22. It's not rocket science. Tom Wilson book clearly lays out what needs to be done. If one can follow a detailed recipe and have a sense of self imposed quality control, it is pretty easily done. Luckily, I started with a fresh new set of Webers and guidance from someone in the know to guide me. It was a 1.7L converted to 1911 and it all turned out great! Engine won't melt down on a test stand with no load unless it's being run at WOT for extended period and running lean and/or detonating. Seems OP at least realized something is wrong stopped to investigate. That is the correct thing to do. Previous post by Mark Henry is a sound plan of action and clearly outlines the preconditions that need to be addressed before trying to run it again. I just hate to see this guy end up like the other guy who had too build his second $$$$$ big /4 because a rod bearing was not secure and melted the thing down .the 1st time around. Dont learn on a type 4 build a few dozen stock 1600s And then tweak your teener engine. Its way cheaper to get a experienced person then to screw it up Dude, Why so negative? You don't hate to see it, you hope it happens! that is why you are here, lurking for bad news. You know nothing about me, about my background, my situation, or this engine. This is not my first rodeo. I have screwed up before and I will screw up again. So take the advice of everyone's grandma and " if you don't have something nice to say, STF". Here you are in the "garage" giving people advice to " pay someone else to do it" Well find that forum and go play big boy with them. I am here to learn from the experts and the people that are willing to pass on their mistakes. And I do thank THEM for chiming in, you?? not so much. |
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