i don't know if i missed it, but did you prime the engine before you set the valves? the valves could be to tight...if your not 100% sure about the cam timing i would suggest that you recheck it before you hurt it!!!jesse
sbc issue, need help!
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it sounds like you've built a few engines before so i'm ASSuming :lol: the assembly was done right and that there's a manufacturing error somewhere. it sounds like the cam gear is on wrong relative to the crank. if you have a degree wheel and dial gauge i'd set them up and check the actual cam timing. i have a feeling it's 90* off.
or you could just set it to TDC and watch the valves to see when they open relative to the crank. you may want to paint lines on the crank every 90* to make it easier.
or you could just set it to TDC and watch the valves to see when they open relative to the crank. you may want to paint lines on the crank every 90* to make it easier.
what pushrod length are you using? if they are way too long that will keep the valves open. unlikely, but possible.
Are you 100%..... 10,000% sure the lifters are hydraulic. This exact same thing happend to me when my friend & I got done with my 355 for my Cutlass.
I had ordered a Herbert cam & hydraulic lifter set. Never even gave the lifters a second look. Set them to zero lash + 1/2 turn, got everything else ready to go, cranked & cranked on the mother fuc*er & NOTHING!!
We checked & tripple checked everything, compression tested it, & 0 CR on all cylinders. WTF!?!?! So, at 2 A.M. we're both tired as Hell but not gonna give up at this point. Finally we suspected solid lifters, so we loosened up all of them, set them to .015 just to get it close & viola!!, had 170 PSI cranking CR & the engine fired right up.
Here, the Doug Herbert Co. had F'd-up & set me solid lifters & not hydraulic. I called 1st thing the next day & explained the situation & they admited the mess-up & gave me a free set of hydraulics.
Of course the rockers are gonna move & everthing will look cosher, but if they are solid lifters, the valve will be hanging open.
Sorry for being long winded, but loosen just one cylinders rockers to give it some lash & then check that cylinder for compression. Mistakes are made & my guess/opinion is that whoever you got the cam & lifters from goofed & sent you solids.
I had ordered a Herbert cam & hydraulic lifter set. Never even gave the lifters a second look. Set them to zero lash + 1/2 turn, got everything else ready to go, cranked & cranked on the mother fuc*er & NOTHING!!
We checked & tripple checked everything, compression tested it, & 0 CR on all cylinders. WTF!?!?! So, at 2 A.M. we're both tired as Hell but not gonna give up at this point. Finally we suspected solid lifters, so we loosened up all of them, set them to .015 just to get it close & viola!!, had 170 PSI cranking CR & the engine fired right up.
Here, the Doug Herbert Co. had F'd-up & set me solid lifters & not hydraulic. I called 1st thing the next day & explained the situation & they admited the mess-up & gave me a free set of hydraulics.
Of course the rockers are gonna move & everthing will look cosher, but if they are solid lifters, the valve will be hanging open.
Sorry for being long winded, but loosen just one cylinders rockers to give it some lash & then check that cylinder for compression. Mistakes are made & my guess/opinion is that whoever you got the cam & lifters from goofed & sent you solids.
Ok, so you put in pistons, but how about piston rings??? LOL
Sounds like somewhere in the valvetrain. Possible solid lift valves. Were the lifters soaked in oil first to pump them up? If not and you went zero lash plus 1/2 turn the valves may be open.
Sounds like somewhere in the valvetrain. Possible solid lift valves. Were the lifters soaked in oil first to pump them up? If not and you went zero lash plus 1/2 turn the valves may be open.
i confirmed last night that we used hydrolic lifters and not solids. i am still thinking we are off on the cam gear but its a bit of work not knowing that it is the issue for sure.... we are going to look further into this weekend
hmm....... i know that it could not have been that far off unless the timing set has something wierd going on with it.....
sbc help
don't you think it's time to get this b*tch running? now you sound like you know your way around a car so you know that it takes three things to run,compression,fuel and spark.....to find your problem is to go back to the basics if you have no compression there are just a few things that can cause it and they all start with the cam an crank timing.. if you wan't to get this thing running you have to make absolutely sure of it so i don't see anyway of getting around pulling the cover..the reason i asked about priming the engine is because the lifters need to be pumped up before you adjust them..otherwise they will be to tight an may be holding the valves open, you check this by backing off the rockers if you still don't have compression after that you have to pull the cover... i hope you don't have what happened to me on the best motor i ever built and thinking i'm the best mechanic in the world
needless to say while using a double roller chain i wasn't paying enough attention because they comes with three key ways but for some reason that i'll never understand there was a casting flaw that looked like a dot to me so i lined it up and called a friend over to check it for me and he said {looks good to me} to make a long story short..buy the time i found my mistake it cost me a hundred and five dollar piston, two broken valves and a bunch of bent valves and a lot of work..... so if there's one thing i learned from this is that anyone can make a mistake at anytime so if i would have pulled the cover first instead of last i could have saved myself a lot of time and money 😳 oh by the way do you know what the meaning of an [EXPERT] is? an ex is a has been and a spurt is a drip under pressure 🙂 let me know if this helps you...jesse
don't you think it's time to get this b*tch running? now you sound like you know your way around a car so you know that it takes three things to run,compression,fuel and spark.....to find your problem is to go back to the basics if you have no compression there are just a few things that can cause it and they all start with the cam an crank timing.. if you wan't to get this thing running you have to make absolutely sure of it so i don't see anyway of getting around pulling the cover..the reason i asked about priming the engine is because the lifters need to be pumped up before you adjust them..otherwise they will be to tight an may be holding the valves open, you check this by backing off the rockers if you still don't have compression after that you have to pull the cover... i hope you don't have what happened to me on the best motor i ever built and thinking i'm the best mechanic in the world
needless to say while using a double roller chain i wasn't paying enough attention because they comes with three key ways but for some reason that i'll never understand there was a casting flaw that looked like a dot to me so i lined it up and called a friend over to check it for me and he said {looks good to me} to make a long story short..buy the time i found my mistake it cost me a hundred and five dollar piston, two broken valves and a bunch of bent valves and a lot of work..... so if there's one thing i learned from this is that anyone can make a mistake at anytime so if i would have pulled the cover first instead of last i could have saved myself a lot of time and money 😳 oh by the way do you know what the meaning of an [EXPERT] is? an ex is a has been and a spurt is a drip under pressure 🙂 let me know if this helps you...jesse
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