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Topic Review (Newest First)
02-27-2013 08:59 PM
vinniekq2 eventually you will get the engine right
02-27-2013 08:40 PM
02-03-2013 07:30 AM
savage9scorpio so upon inspection of things. the timing had backed off a bit(distributor twist) the car still has a sound coming from the right side but it sounds as if a cylinder isn't firing. I'm gonna change the spark plugs wires whenever I get some more $$$.
the car has some of its grunt off idle again but there's a vibration/missing sound which might b tht side I mentioned. can't complain 2 much about the motor. tho, anything is better than tht 307 it had before.

02-03-2013 07:22 AM
1Gary What we used while run testing engines to sounding out engines at the factory was what we called a "sound bar". Basically it is a pc of solid round stock with a wooden file handle pounded on one end of it and a semi point on the other end. I like that method because going to a metal scrap yard you can make it as long as you want to reach areas normally you wouldn't be able to and they are cheap to put together.

But at the end of the day,you still have to be able to know what your listening to.
02-02-2013 11:28 PM
newly rebuilt sbc 400 1st problems

Originally Posted by savage9scorpio View Post
not disgusted. distraught. I will check all of those shortly I have my dad driving over now to check a few things. I just surely hope it isn't a rod already. I just went outside and I kno its coming from the left right side(passenger). I pulled a few spark plugs while it was running to see if a cylinder was dead but after getting zapped by the sparkplugs a few times and seeing no change I paused and came into get warm.
A tool is made for removing spark plug wires that are insulated so that will not happen. The auto parts store also has a stethascope to listen to the engine noises that would be less shocking. Have someone start the engine, hold their foot on the brake and shift the transmission from reverse to forward gear. You will have to be close to the drive shaft to see and hear if the universal joints are bad. Also check your flexplate for cracks or if it is making any noise. Be safe and put the vehicle up on jack stands.While your down there at the flexplate use your stethascope on the oil pan and the side of the block the noise is coming from.
02-02-2013 11:12 PM
newly rebuilt sbc 400 1st problems

Anyone that has a hydraulic flat tappet camshaft should purchase some brand of Engine break-in oil. You can use Royal Purple, Brad Penn, Comp Cams, Joe Gibbs Racing. Now after break-in you can use your brand of motor oil (except synthetic) with ZDDP Plus additive added to it. There is no exceptions or you will wipe the lobes off you camshaft. Read this Wiki article on adjusting valves to make sure you are doing them correctly. Here is another Wiki article on tuning the advance curve for your performance engine. Also explains how to set your engine timing.
02-02-2013 10:20 PM
vinniekq2 when the car is idling,spit on each header tube,look for a cold tube
02-02-2013 02:24 PM
This is a link for cam break in my memory was not all that bad. I had no idea about cam break in myself until I decided to read the direction that came with the cam(was only cam I ever installed)
02-02-2013 02:20 PM
bigblockragtop There is a process to break in the cam, off the top of my head I had a new cam a while back and the process was to run the engine at 2000 or 2500(you will have to check with who makes your cam) for 20 minutes(again not sure) dump the oil and new oil and go. Check for exhaust leaks too sometimes they can sound like an engine noise. I am only a home owner type mechanic and only have limited experience so I would not want to give you bad advice.
02-02-2013 01:28 PM
savage9scorpio I'm not sure if it was done properly. would an issue with the cam b heard from one side of the motor tho? I have duals so I can hear a distinct difference on tht certain side.
I kno I had been looking for the oil with the zinc but couldn't find any. the cam is pretty big for a hyd flat tappet imo. and the valves wernt adjusted till the other day been driving it for about 2 weeks side so. .

car looks cool = Thanks sir
02-02-2013 12:47 PM
bigblockragtop You said the engine was just built. Did you do a proper cam break in? You can destroy a cam quickly if not. If it a roller cam that does not apply. You will get it. Car looks cool too.
02-02-2013 12:30 PM
savage9scorpio not disgusted. distraught. I will check all of those shortly I have my dad driving over now to check a few things. I just surely hope it isn't a rod already. I just went outside and I kno its coming from the left right side(passenger). I pulled a few spark plugs while it was running to see if a cylinder was dead but after getting zapped by the sparkplugs a few times and seeing no change I paused and came into get warm.
02-02-2013 12:20 PM
bigblockragtop First off do not get disgusted. We all go through this. The valve covers being lose will cause oil loss and as long as you did not run the oil low you should be fine besides waiting for all that oil to burn off the exhaust. You need to check into the linkage for the tranny and have that set properly then go from there. You are saying you lost power, so recheck the basics such as the timing it may have moved, maybe it was not tight enough. As far as the noise goes it does not sound like it is the engine if it makes a(singualar) noise then it could be anything from a bad motor mount to an exhaust hitting somewhere.Watch under the hood while someone puts it in gear and touches the gas lightly with a foot on the brake and then do it in reverse to see if you can pinpoint the noise. Just be patient and do one step at a time. If you were running in first it would make the car feel a lot more responsive. Check the fluid in the tranny see if it smells burnt. Ls motor swaps are not easy either and dollar for dollar you can get more hp with a big block(for now anyway).
02-02-2013 11:50 AM
newly rebuilt sbc 400 1st problems

so since I've had the motor rebuilt the only thing that was giving me problems was tht the shift cable to the powerglide wasn't hooked up. so I was having to manually listen till the rpm's sounded like it was time to shift, let off the gas and hope it went into 2nd. tht problem still is happening but now already the motor has lost power.

the other day me and my dad got the distributor timing down and another day got the rockers arms adjusted. I think the valve covers were loose on the way home from his house because once I got off the highway I saw vapors of smoke billowing into the car. I'm not sure if I have burned a valve or 2. or if one of my rods are loose somehow.

it doesn't have its grunt from idle on up anymore and now whenever I do get it to shift into second I hear a tick or clap or clunk noise from the right side of the motor. this also happens if I'm on the highway cruising and then let off the gas briefly.ive heard it 3 or 4 times so far

1:trans wasn't shifting by itself so 1st gear rpm may have overdone/overcooked on of the rods.
2:having the valve covers loose for 2 unknowing days.

anyways besides tht I'm distraught and feel like I shoulda just went forth with the ls swap which I still might do if this motor is done already.

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