Won't start after H/C install
Thread Starter
Melting Slicks
Joined: Jun 2005
Posts: 3,088
Likes: 61
From: NY- 2013 Corvette Challenge Champion-2013 Index Combo Champion 2015 CC/MM Champion
St. Jude Donor '07
Won't start after H/C install
Tried starting after H/C,LS6 intake,UD pulley,3.73 gears.It tried to run a few seconds and popped a few times out the exhaust.Tried again and it just turns over,sounds like it wants to fire,but nothing. Checked a plug it was soaked with gas,pulled the relay for fuel pump so it wouldn't flood it out,tried to start,popped a few times but nothing.Checked compression on one plug,200psi,compression is good.Or should I checked all 8 cylinders? I dialed in the cam,dead nuts on,I got 1 code P1571 H C, What do you guys think?
Drifting
Joined: Oct 2003
Posts: 1,540
Likes: 0
From: bloomfield nj
Originally Posted by DRIVER456
Tried starting after H/C,LS6 intake,UD pulley,3.73 gears.It tried to run a few seconds and popped a few times out the exhaust.Tried again and it just turns over,sounds like it wants to fire,but nothing. Checked a plug it was soaked with gas,pulled the relay for fuel pump so it wouldn't flood it out,tried to start,popped a few times but nothing.Checked compression on one plug,200psi,compression is good.Or should I checked all 8 cylinders? I dialed in the cam,dead nuts on,I got 1 code P1571 H C, What do you guys think?
200 psi? can't be.regardless,are you sure the valves aren't being held open? depending on your cam,maybe your pushrods are too long.i'm assuming the cam is timed right. 1571 set probably because the engine started while you were still holding it in crank.
Thread Starter
Melting Slicks
Joined: Jun 2005
Posts: 3,088
Likes: 61
From: NY- 2013 Corvette Challenge Champion-2013 Index Combo Champion 2015 CC/MM Champion
St. Jude Donor '07
Its an old gauge,so it could be off.Whats normal compression?I'll check all 8 cyl. on Saturday.
Drifting
Joined: Oct 2003
Posts: 1,540
Likes: 0
From: bloomfield nj
Originally Posted by DRIVER456
Its an old gauge,so it could be off.Whats normal compression?I'll check all 8 cyl. on Saturday.
depending on mileage-anywhere between 155-165.i'm assumng the bottom end is still original.are you sure the cam is timed right?
Thread Starter
Melting Slicks
Joined: Jun 2005
Posts: 3,088
Likes: 61
From: NY- 2013 Corvette Challenge Champion-2013 Index Combo Champion 2015 CC/MM Champion
St. Jude Donor '07
Originally Posted by dpd
depending on mileage-anywhere between 155-165.i'm assumng the bottom end is still original.are you sure the cam is timed right?
Is it possible it went to 200psi because the cylinders filled up with gas?
Thread Starter
Melting Slicks
Joined: Jun 2005
Posts: 3,088
Likes: 61
From: NY- 2013 Corvette Challenge Champion-2013 Index Combo Champion 2015 CC/MM Champion
St. Jude Donor '07
Originally Posted by dpd
how did you adjust the valves?you should have adjusted them all in 2 crank revolutions.are you sure they not hung open?
Drifting
Joined: Oct 2003
Posts: 1,540
Likes: 0
From: bloomfield nj
with 1 ready to fire[dots on cam don't line up]adjust both valves on 1,ajust the exhausts on 2-7-8,intakes on 3-4-5.spin it over[6 ready to fire],adjust both valves on 6,adjust the intakes on 6-7-8,exhausts on 3-4-5
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Top 10 Corvette Engines RANKED by Peak Torque (70+ Years of Muscle!)
Joe Kucinski
Corvette ZR1X Will Be Pacing the Indy 500, And Could Probably Race, Too!
Verdad Gallardo
Top 10 Corvettes Coming to Mecum Indy 2026!
Brett Foote
Top 10 C9 Corvette MUST-HAVES to Fix These C8 Generation Flaws!
Michael S. Palmer
10 Revolutionary 'Corvette Firsts' Most People Don't Know
Joe Kucinski
5 Reasons to Upgrade to an LS6-Powered Corvette; 5 Reasons to Stay LT2
Michael S. Palmer
2027 Corvette vs The World: Every C8 vs Its Closest Competitor
Joe Kucinski
Burning Brakes
Joined: Oct 2000
Posts: 832
Likes: 0
This exact thing is happening to me, I'll be watching this closely as I'm stumped myself! I can get mine to start, but I have to crank, turn key off, crank, turn key off etc. and it will try to start and then finally catch. But there is popping out the exhaust until it smooths out. My plugs were saturated too. Anyway, hopefully we can get this diagnosed. Mine is a 99 FRC 
Thread Starter
Melting Slicks
Joined: Jun 2005
Posts: 3,088
Likes: 61
From: NY- 2013 Corvette Challenge Champion-2013 Index Combo Champion 2015 CC/MM Champion
St. Jude Donor '07
Originally Posted by hightest
Sounds like the valves are hung open.
Recheck you're rockers.
Hopefully you're cam isn't so big, or your pushrod length isn't off that you're valves are hitting the pistons.
Recheck you're rockers.
Hopefully you're cam isn't so big, or your pushrod length isn't off that you're valves are hitting the pistons.
Thread Starter
Melting Slicks
Joined: Jun 2005
Posts: 3,088
Likes: 61
From: NY- 2013 Corvette Challenge Champion-2013 Index Combo Champion 2015 CC/MM Champion
St. Jude Donor '07
Yes I am.Just want to see what somebody else thinks before I remove the front part of the engine and check the cam.
Thread Starter
Melting Slicks
Joined: Jun 2005
Posts: 3,088
Likes: 61
From: NY- 2013 Corvette Challenge Champion-2013 Index Combo Champion 2015 CC/MM Champion
St. Jude Donor '07
Originally Posted by dpd
what did you come up with? recheck your faults.
Drifting
Joined: Oct 2003
Posts: 1,540
Likes: 0
From: bloomfield nj
i'm going to assume compression is ok and the pushrods are not holding the valves open.when you installed the cam,did you line up the dots or did you have them both going up at 12 o' clock?
if you take off both valve covers and bring #1 to top dead center to fire,both valves on #1 should be closed and #6 cylinder should be on overlap[end of exhaust stroke,intake valve should just be opening and the exhaust valve should be closing].if the valves AREN'T hung open,you probably are 180 degrees out of time,with the dots lined up #6 cylinder fires,with them both up at 12 o clock,1 fires.since there is no distributer the cam sensor and crank sensor have to match.with that being said,the valve adjustment would have to be off if you are 180 out also.
are you sure you don't have any faults? did you reattach the grounds on the back of the head[left one]?
if you take off both valve covers and bring #1 to top dead center to fire,both valves on #1 should be closed and #6 cylinder should be on overlap[end of exhaust stroke,intake valve should just be opening and the exhaust valve should be closing].if the valves AREN'T hung open,you probably are 180 degrees out of time,with the dots lined up #6 cylinder fires,with them both up at 12 o clock,1 fires.since there is no distributer the cam sensor and crank sensor have to match.with that being said,the valve adjustment would have to be off if you are 180 out also.
are you sure you don't have any faults? did you reattach the grounds on the back of the head[left one]?
Last edited by dpd; Feb 11, 2006 at 03:27 PM.
Thread Starter
Melting Slicks
Joined: Jun 2005
Posts: 3,088
Likes: 61
From: NY- 2013 Corvette Challenge Champion-2013 Index Combo Champion 2015 CC/MM Champion
St. Jude Donor '07
Originally Posted by dpd
i'm going to assume compression is ok and the pushrods are not holding the valves open.when you installed the cam,did you line up the dots or did you have them both going up at 12 o' clock?
if you take off both valve covers and bring #1 to top dead center to fire,both valves on #1 should be closed and #6 cylinder should be on overlap[end of exhaust stroke,intake valve should just be opening and the exhaust valve should be closing].if the valves AREN'T hung open,you probably are 180 degrees out of time,with the dots lined up #6 cylinder fires,with them both up at 12 o clock,1 fires.since there is no distributer the cam sensor and crank sensor have to match.with that being said,the valve adjustment would have to be off.
are you sure you don't have any faults? did you reattach the grounds on the back of the head[left one]?
if you take off both valve covers and bring #1 to top dead center to fire,both valves on #1 should be closed and #6 cylinder should be on overlap[end of exhaust stroke,intake valve should just be opening and the exhaust valve should be closing].if the valves AREN'T hung open,you probably are 180 degrees out of time,with the dots lined up #6 cylinder fires,with them both up at 12 o clock,1 fires.since there is no distributer the cam sensor and crank sensor have to match.with that being said,the valve adjustment would have to be off.
are you sure you don't have any faults? did you reattach the grounds on the back of the head[left one]?
I'll be back later and let you know.Thanks................Paul
Le Mans Master
Joined: Mar 2004
Posts: 5,562
Likes: 5
From: South East coast Florida
It's been awhile for me, but aren't you supposed to turn over the engine for 2 Crank revolutions and verify the Cam/crank dots return in-line? This say's you are truly timed properly, and not 180 degrees off.
Last edited by mowton; Feb 11, 2006 at 03:44 PM.
Drifting
Joined: Oct 2003
Posts: 1,540
Likes: 0
From: bloomfield nj
ok,if you lined it up dot to dot,#6 was firing[i think the manual has it like that].#1 is in overlap.i think you adjusted the valves 180 out.your cam is not out[it shouldn't really matter because there is no distributer,the cam/crank sensors know the difference from the reluctor rings on the cam/crank].but if you adjusted the valves thinking that the dots lined up was #1 firing then you adjusted the valves 180 out.
as long as i know chevy motors were always weird like that,#1 firing was cam/crank dots at 12 o clock.
as long as i know chevy motors were always weird like that,#1 firing was cam/crank dots at 12 o clock.