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The rebuild of the Pantera coloured 509+some hull work
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After one really great summer with almost no mishaps with the Pantera it became time for the 509 to get a, well deserved, rebirth.
Top speed during the summer was 77,5mph on GPS which is very low for the Factory 1 Pantera with an engine that is supposed to produce 720-740 crank HP. When the engine was all new Dave @ MDG Performance (the engine builder) ran 84mph on the test run and Jo Nuņez and BJ Maher are supposed to have run 89mph. We have now started taring down the engine and have done a compression test and a cold leak down. We never started it before the test just ran it on the starter for a total of a couple of minutes. So the leak down might be a bit off. Leak Down 1: 25% | 38% 2: 19% | 21% 3: 80% | 80% 4: 53% | 55% 5: 60% | 60% 6: 27% | 38% 7: 42% | 48% 8: 23% | 34% Compression (not the static comp...) 1: 10,1 psi | 10,7 psi 2: 10,8 psi | 10,9 psi 3: 07,0 psi | 08,0 psi 4: 10,7 psi | 11,0 psi 5: 09,4 psi | 10,0 psi 6: 10,6 psi | 10,6 psi 7: 10,5 psi | 10,9 psi 8: 10,3 psi | 10,4 psi |
Re: The rebuild of the Pantera coloured 509
According to the leak down the valves seems to be fine but the rings is either totally waisted or they are stuck in the pistons (the engine hasn't been run for about three months). Altough we had the pistons about 25deg before TDC and forced them up to TDC against the air pressure, to get the rings to live - then got the reading.
The heads are going off tonight, then we'll see what it looks like. Pics to come! |
Re: The rebuild of the Pantera coloured 509
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Also it's pretty milky in the valve valley and in the valve covers, during summer there was most of the time some cream coming out of the valve vents.
The oil on the dipstick is absolutely flawless, changed the oil 3-4 times during summer and it looked great every time. |
Re: The rebuild of the Pantera coloured 509
Originally Posted by tomas_wallin
(Post 1987475)
during summer there was most of the time some cream coming out of the valve vents.
But the engine run pretty cold during the sumer? |
Re: The rebuild of the Pantera coloured 509
Originally Posted by Mange
(Post 1987497)
Yeeah, I remeber that. Even tasted like Cafe au Lait :-)
But the engine run pretty cold during the sumer? Yes on the normal runs I beleive it ran pretty cold, but on the other hand on harder runs it ran pretty hot. The only time we really measured the oil temp was during a long run at about 74-75mph (wot is at 77,5mph) and got 280F... |
Re: The rebuild of the Pantera coloured 509
Tomas, What size are your carbs? What kind of boost were you running?
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Re: The rebuild of the Pantera coloured 509
Hey Tomas Wallin, I think that the milky ness is pretty normal if your motor runs really cool. As long as the oil is clean and normal I think it's ok. I think it just the condensation building up under the valve cover. I was having the same problem in my 22 classic Donzi with a worked 454. The oil looked great every time I changed it, but there was some chocolate milk type stuff under the valve cover. I went with a higher (180) thermostat to burn off the condensation and it worked. Just throwing in my 2 cents.
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Re: The rebuild of the Pantera coloured 509
I had the same thing happening on my 28 when I ran it.
The oil in the lower end looked good but on the inside of the valve covers & lifter valley it was milkshaked. Thomas's description of Irish coffee summed it up great. My first thought was Condensation due to low oil temp so what I done was clean off the inside of the valve covers & heads , rockers ect also give it a quick oil change the best I could ( It held 14 quarts , 3 oil filters & oil running through both of the turbo's as well. ) So that is what I mean by the best I could. As I am shure there was some oil in a few of the lines that didn't get completly drained. Then I bypassed the oil cooler & ran it for a little while to see what happened & it still happened. It was the end of the season here when I was doing this & I ended up pulling the power over the winter & selling the boat so I never really got a definate on what it was doing. However in my situation I feel it was the good old copper headgaskets seaping & staying in the upper end of my motor, or it could have been a combination of both for that matter. |
Re: The rebuild of the Pantera coloured 509
Tomas , Have you tore your motor down yet & ifso what kind of headgaskets where on it ? Also was the block oringed & the heads reciever grooved ? The reason I ask is I am putting my Supercharged 511 back togather & I have been doing as much research as I can on my headgaskets because I don't want to deal with the normal leaky copper gasket situation. If I was starting from scratch I would just run a MLS Cometic gasket & be done with it , However since my shortblock is still togather & the block is already ringed I cannot run the MLS so I will be going another route. I have been talking to Dean Gellner from Gellner engenering & I think we have the problem solved. Let me know if your engine is grooved & oringed & ifso I will be glad to pass along any info that I have on the subject. Talk to you later , Scott
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Re: The rebuild of the Pantera coloured 509
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tomas, this helped me get rid of condensation.
Works great, but grab your wallet |
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