all right i have posted earlier, i have been told what caused my engine to tulip four intake valves was too small of a carb(ran a holly 650 dp). so now i am in the process of trying to find a 750 or bigger. my machine shop told me it is better to go too big and jet down! he also said i cant use my 650 and jet up because i cant get the air flow through it!
i am running an olds 455 30 over with a comp cam .490 intake .490 exaust and just under 10-1 compression. also a 1975 mallory marine mechanical advance distributor.
my engine was rebuilt the summer of 03. it has been the most reliable boat i have ever had!! when i was rebuilding it i did alot of reseach on olds(thank god). i definatley built the bottom end right!
heres the deal, last winter i dumped a bunch of $ into my boat. i had my holly 650 dp rebuilt. it used to be hard starting and it wouldnt idle without loading up.
i also had the distributor rebuilt. the timing was jumping around a little with the timming light on it. i thought it was the chain getting sloppy so i replaced it(i could tell it didnt need one, but i was already there so i replaced it anyway).the only thing left to alow the timming to jump around(timming light)is the distributor. so i had that rebuilt. the guy told me that he made it a little more snappy for me and that i would like it. he also told me the most he could get out of it was 8 degrees. i set my timming at 34 @ 3000rpms, and went boating.
i have had my boat in four times since the carb, distributor rebuild.the thing ran and idled great. on the fourth day about half way through the day it started coughing every once in a while. nothing big(i thought) i just have a little water in my carb.it ran great all the way back to the launch, dropped of someone to go get the trailer, idled for 10 minuts perfectly then died. i didnt even try to start it because i knew there was water in my carb.
NOT, i tuliped 4 valves
so i have the heads back from the machine shop. he went through (machined) and replaced everything.
i dont want to do this again!
so i have been told to replace my carb with a bigger one. tony @ skagen marine told me i can jet my 650 dp to work just fine(keep my combustion chamber temp from spiking).
so just today i was told that my distributor may be the culprit. too much advance too quick???
i screwed something up, between my carb or dist rebuild, how do i make sure i dont melt my valves again?? i am not rich i am an unemployed carpenter!!!!!!!!!!!