Register or Log In To remove these advertisements. |
|
|
|
Thread Tools | Display Modes |
05-09-2012, 03:45 PM | #51 | |
Registered User
Join Date: Mar 2010
Location: Minnetonka, MN
Posts: 409
|
Re: rattle rattle thunder clatter boom boom boom...
Quote:
currently the truck doesn't smoke, and runs well, so i'd think internally things are in fairly good shape and i'd get away with just making sure nothing is warped and throwing gaskets at it and slapping her back together. then i could save the cash for a crate 350 or core big block to rebuild for when this motor pukes again in the future. i guess i am asking if i am setting myself up for a short term disaster if I DON'T have the heads inspected while they are out of the truck? I'd like to get a couple years down the road before having to pull the top end again.
__________________
1971 C-20 350/350 |
|
05-09-2012, 03:59 PM | #52 |
Registered User
Join Date: Nov 2007
Location: Hermiston, OR
Posts: 947
|
Re: rattle rattle thunder clatter boom boom boom...
Having the heads magnafluxed (aka "magged") is not that expensive. Most of the time involved is removal of the valvetrain parts.
__________________
Running in place gets you nowhere fast. -me 1968 GTO 4-spd covnvertible 1970 K-20 4-speed, factory AC. |
05-09-2012, 04:09 PM | #53 |
Newbee
Join Date: Jan 2010
Location: Phoenix, Arizona
Posts: 1,406
|
Re: rattle rattle thunder clatter boom boom boom...
Clean the big chunks off with a razor scraper, gasket scraper, or a sharpened putty knife. Take your time, and do not remove any metal, dont gouge anything. Then clean it up with your scotchbrite. I wouldn't go crazy trying to remove a bunch of carbon from the heads. Make sure to remove all of the scrapings from the cylinders, and lifter valley before bolting it back together.
If nothing is obviously wrong, put it back together as is. The most you will lose is a few gaskets. Small blocks are pretty darn tough. |
05-09-2012, 06:01 PM | #54 |
E.H.F.D Engine #2
Join Date: Feb 2003
Location: East Hampton, NY Long Island
Posts: 916
|
Re: rattle rattle thunder clatter boom boom boom...
One time on my 03 2500HD, CarQuest sold me a new starter, the part number on the box was correct, but the part number on the actual starter was wrong. It bolted up and worked fine, but when you got into it, or had a load, the flex plate was hitting the starter gear. (The gear on the wrong starter didnt retract far enough) Sounded similar to that. Whether its the starter or not, i'd definitely say you have an issue with the flex plate or something in that general vicinity
__________________
-NICK '72 K10 SWB Fleetside. Avocado Highlander 350-4speed-NP205 Frame Off Re-Creation '89 GMC V3500 C/C Flatbed Plow Truck 454/SM465/Np205 '15 Chevy 2500HD CCSB High Country Duramax '22 Tahoe Premier Duramax |
05-09-2012, 08:43 PM | #55 |
Senior Member
Join Date: Aug 2002
Location: Valley Center KS
Posts: 3,524
|
Re: rattle rattle thunder clatter boom boom boom...
What do I win for having the right answer? :-) glad you found the issue
|
05-10-2012, 10:28 AM | #56 | |
Registered User
Join Date: Mar 2010
Location: Minnetonka, MN
Posts: 409
|
Re: rattle rattle thunder clatter boom boom boom...
Quote:
I'll fashion a trophy for you out of the old copper gaskets I was working on cleaning up the mating surfaces last night and also noticed a very small area between #2 and #4 on the other gasket that looked suspect. that could also be the reason for the lower compression on those two cylinders. I think the mystery is all coming together. I also ran a straight edge over all the mating surfaces and they are flat as can be, so no warpage. now i guess it's time to get it all put back together...
__________________
1971 C-20 350/350 |
|
05-10-2012, 07:04 PM | #57 |
E.H.F.D Engine #2
Join Date: Feb 2003
Location: East Hampton, NY Long Island
Posts: 916
|
Re: rattle rattle thunder clatter boom boom boom...
DUH i somehow thought this post was new yesterday, and missed the part where you found the head gasket problem. Disregard my post!
__________________
-NICK '72 K10 SWB Fleetside. Avocado Highlander 350-4speed-NP205 Frame Off Re-Creation '89 GMC V3500 C/C Flatbed Plow Truck 454/SM465/Np205 '15 Chevy 2500HD CCSB High Country Duramax '22 Tahoe Premier Duramax |
05-14-2012, 11:15 PM | #58 |
Registered User
Join Date: Mar 2010
Location: Minnetonka, MN
Posts: 409
|
Re: rattle rattle thunder clatter boom boom boom...
Well, got her all back together and she won't stay running. I think I adjusted my valves too tight, or the timing is way off... I installed a new balancer and thought I got top dead center on the intake stroke before setting the valves, but maybe not? TDC should be just after the intake valve closes right? I think i am going to use the EOIC method tomorrow and see if that helps. right now I am too dejected to try anything tonight.
Can anyone tell if the timing is off based on which valves are open/closed in the following picture? You can see the black mark on the distributor body that lines up with the rotor, and the white TDC mark on the balancer... i'm stumped.
__________________
1971 C-20 350/350 |
05-15-2012, 01:21 AM | #59 |
laying low
Join Date: Mar 2001
Location: Searcy, Ark. USA
Posts: 13,514
|
Re: rattle rattle thunder clatter boom boom boom...
How long does it run when started and is it smooth or missing?
True the valves appear to be closed, the rotor is close to that mark and the harmonic balancer mark is on. If the engine starts cold but after getting up to normal temp it shuts down it may well be tight valves. You could loosen each one 1 turn or so then try startup again and see how it runs. If it stay running or runs longer then you are on to it. I've always preferred the hot running adjustment method. I've always had great results with it. It is messy but it will clean up. Are you familiar with this method?
__________________
Boog 69 Chevy stepside, 358/T350, 4.11 posi, 4.5/4 drop, rallys, poboy driver primer is finer 91 Chevy sportside, Tahoe, Yukon & GMC Crewcab All GM..'nuff said. I stand for the flag and kneel at the cross |
05-15-2012, 01:25 AM | #60 |
Registered User
Join Date: Nov 2007
Location: Hermiston, OR
Posts: 947
|
Re: rattle rattle thunder clatter boom boom boom...
How did you adjust the valves this time?
__________________
Running in place gets you nowhere fast. -me 1968 GTO 4-spd covnvertible 1970 K-20 4-speed, factory AC. |
05-15-2012, 01:39 AM | #61 |
Registered User
Join Date: Mar 2010
Location: Minnetonka, MN
Posts: 409
|
Re: rattle rattle thunder clatter boom boom boom...
[quote=Boog;5381295]How long does it run when started and is it smooth or missing?QUOTE]
It doesn't run...sounds like it is hitting on a couple cylinders if i keep my foot on the pedal but it won't idle...just dies. I adjusted the valves according to the Haynes manual. found TDC on #1, took out the lash + 1 full turn on both, then turned the crank 90* to the next one in the firing order.
__________________
1971 C-20 350/350 |
05-15-2012, 09:10 AM | #62 |
laying low
Join Date: Mar 2001
Location: Searcy, Ark. USA
Posts: 13,514
|
Re: rattle rattle thunder clatter boom boom boom...
1. Make sure you have the plug wires in the correct firing order.
2. Loosen each rocker one full turn and give it a try.
__________________
Boog 69 Chevy stepside, 358/T350, 4.11 posi, 4.5/4 drop, rallys, poboy driver primer is finer 91 Chevy sportside, Tahoe, Yukon & GMC Crewcab All GM..'nuff said. I stand for the flag and kneel at the cross |
05-15-2012, 11:28 PM | #63 |
Registered User
Join Date: Mar 2010
Location: Minnetonka, MN
Posts: 409
|
Re: rattle rattle thunder clatter boom boom boom...
She's alive!
I re-did the rocker adjustments using the EO-IC method and she fired right up! I hear a little tiny bit of chatter in the top end, so to sleep easy i am going to adjust the valves while it's running... Now, the timing was set dead on the nuts @ 0* so it ran like crap, and the hand me down timing light that must be 35 years old and i have never used didn't work (go figure) so I timed it by ear just to smooth it out until i can rent a good light. I think I understand the timing processes, but can you guys offer up any tips?
__________________
1971 C-20 350/350 |
06-06-2012, 11:58 PM | #64 |
Registered User
Join Date: May 2012
Location: Nor Cal, CA
Posts: 17
|
Re: rattle rattle thunder clatter boom boom boom...
Did you ever get this running? If so, were the head gaskets the only problem? I have the same noise...going to get a compression tester tomorrow.
|
06-07-2012, 12:28 AM | #65 |
Registered User
Join Date: Mar 2010
Location: Minnetonka, MN
Posts: 409
|
Re: rattle rattle thunder clatter boom boom boom...
Yep, she runs like a champ (mostly). The head gaskets were the smoking gun. Blown fully between 3 and 5 and slightly between 2 and 4. (compression test indicated both) I bought a timing light and re-timed it but now it's fairly rough at idle and the timing mark isn't crisp under the strobe so i think maybe the mechanical advance needs to be replaced. Haven't had any time to work it out, and it is driveable, so we'll see when I get to it.
Good luck with yours. I had never had an engine torn down to the block and I got her back together again in just a couple nights of wrenchin.
__________________
1971 C-20 350/350 |
Bookmarks |
|
|