I just tried to start my rebuilt 400... I thought my crank was set on No. 1 TDC when I installed it... I installed the distribtuor and lined up number one on the rotor... upon fire up, she wouldn't fire and started spitting back out the carb... So I decided to check TDC by putting my finger on no.1 hole while cranking motor... at that point I was well away from "0" on my timing pointer and actually 180 degrees from no.1 position on the distributor... thinking my distributor was 180 off, I reversed all the plugs at the distributor... she did fire up, but idled pretty rough... I shut her off to retard the timing and then she bucked and I heard an awful metallic thud noise... thinking pushrod, I removed the valve covers to check for any signs of damage and all looked well... The last thing I did was rotate to find TDC again, this time I was under the truck watching for the "0" mark on the balancer with my finger on the hole to fell the piston compress... I now have her set on TDC, reading "0" on the timing mark and also turned the distributor to contact one again....


I know the post is long, but I am concerned on what might have happened when she fired initially and what the noise was I might have heard... I was thinking real bad detonation... I haven't checked all the plugs, but 1, 2 & 3 looked good with no. 1 looking like it got pretty hot, but not ruined...

my rebuild consists of 400 block bored 0.40, Badger flat tops, 255 Dual Energy Comp Cams timed straight up (dot to dot), performer intake, stock manifolds, edlebrock 4bbl carb 600 cfm... I have 3/4 tank of 92 octane in the tank that is 3 to 4 months old from sitting during the rebuild...

I am also wondering about my intake seal job as I didn't get enough sealer (not using end seals) on the ends initially and had to remove and reinstall. I basically torqued it down, saw the lack of sealer, took it back off, cleaned up and redid sealer and reinstalled manifold..... the intake gasket on the head surface is the felpro with the sealing ridges, so I figured reusing it after only just torqueing it down once wasn't a problem...

I am not giving up on this first motor project, the engine still rotates fine by hand and I hear no binding when cranking it with a remote starter.... any advice or experience is welcomed...

Thanks

 

Allright, I think I got it<!my head outta my a$$>.... I did decide to reinstall the intake again (I just don't trust myself), plus I went over the roller rocker torques again just to be sure (bolt-ons from Ford). Set timing at 3 BTDC, set rotor on no.1 position, and she fired right up....

Being a first timer (like you couldn't tell) my brain goes dead when it starts... I did not check the radiator fluid (put up to 3.5 gallons prior), but did not top it off when it started... well it overheated...

It keeps overheating and I am wondering about the following syptoms... The passenger manifold to exhaust pipe connection seems to leak... I am hearing an audible air hiss (although I didn't plug my dist. vac line, but I doubt it sucks like I'm hearing) and also my new radiator is narrower than what came out of it (24" vs 27.5")... Also no shroud.... It got hot enough to diesel when I shut it off...

Heres what I am planning next... Start her back up (full of fluid again)... double check my initial timing at 650 RPM... (with my dist. vac plugged this time).....spray WD40 around the intake to check for leaks... also I am wondering if the exhaust on the passenger side is creating some restriction by its leaking connection and building up heat.. I have a fan shroud I can steal from another truck... Hopefully I don't ruin this motor before I get it going... How much running can the new cam take before I officially break it in??

Again, any thoughts would be great... As you see I am struggling a little...

 

Overheating is common on new engines. You should have some large floor fans to help keep it cool. You should have a fan shroud or an electric fan on the radiator to get air through it when idling. If you can get it outside, you could run a hose on the radiator to cool it.

 

head gaskets being oriented incorrectly is common too, are you sure you have them in right with the "FRONT" in the front? the cam is considered broken in after the first 20 minutes of running time at 2000-2500 rpm.

 

I have read about adding fans to help cool... the hose idea sounds good.... am I to expect the over-heating to subside at some point after running a while?? If the head gasket were on backward, wouldn't I be blocking cooling passages... I can't say I saw a front stamped on them, but I did make sure the passages were all open and matching... I do get radiator flow when the t-stat open and no leaks, except for the overflow...

Thanks guys

 

supposedly there are tabs that stick out a little on the front of the gaskets. if they are in right you will see them in the front on both sides. the gaskets are different front to rear in that the end passage is blocked off in the rear and open in the front to allow the coolant to flow to the thermostat. hopefully i'm worrying you for nothing, but check it out anyway.

 

A new motor will have a lot of friction, friction produces heat. You may need extra cooling until the parts break-in.

 

Well, I went a got the big Modine radiator - 3 row - 27-1/2" core width... I started with re-checking timing (3 to 4 mins. running) and then went to 2500rpm for cam break-in... After 5 or 6 additional minutes running at 2500 the temp. gauge made the slow climb toward hot again... not wanting to heat her up anymore, I shut it down... it was an improvement from my intial experience however... and I did have a large (but suprisingly wimpy flow) floor fan blowing from the front...

I wondering how to control my heat even better... with new flat-top pistons and higher compression, I know I am probably creating a bit more heat than stock... I gotta tell you though, the thing starts with a vengeance it never had before...

My ideas:

-Replace 195 thermostat with a 180...?

-Defintely need a fan shroud...

-Replace my spacer fan with a clutch type...?

My timing is set around 2 BTDC... The cam is set straight up with a roller timing set... It really wanted to idle even better at "0", but not wanting to advance too far and create more heat I backed it off a little... I did hear some light valve or rocker tapping at 2500 though..... after worrying about the effects of my previous overheat, I decided to pull all the plugs and compression test just to see where I was... the plugs looked tan, but a little sooty, like maybe hotter is better... the cylinders were all around 160 to 170... the results were comforting for a first time motor killer....

I think I am getting closer... I have a good feeling that once I start down the road, overheating won't be an issue, but the idle situation still could be.... I am just trying to get the Cam break-in time in without overheating in the 20-30 min. required... I am going to try again tommorrow since my timing is close and see what happens... maybe I sat at idle too long...

Again, any comments are appreciated...

 

Get a Robertshaw Balanced flow Tstat. 180 degrees is OK. Definitly get a fan shroud. A nice flex fan is OK, but not without that fan shroud. I run a 16" electric pusher in the front of the radiator.

 

You would be amazed at what a decent "fly swatter" and a shroud can do. You need a shroud.

 

Thanks for all your help guys... I scavanged the shroud from my '84 F-150 (although it is too small) clamped her for temporary and ran it around 25 minutes at 2500 rpm before she started climbimg toward the upper end of the gauge this time... should I consider that good enough for cam break-in...? (Compcams sez 30 minutes at 2500 rpm)..... Feeling alot better about my work, I went ahead and put the hood back on and considered it a good night...

I still need to find the right size shroud.... I called about every junkyard in Columbus, Ohio and nobody had anything.... I am considering trying my hand at fabbing something since I have a pretty good template with the smaller one I do have... anybody have any leads...

Thanks again for reading my ramblings, now the test drive... I also had to re-build my first transmission (NP435) due to sloppy input shaft and found a missing needle bearing in the end where it meets the output shaft... the tranny crossmember was also half bolted on and the transfer case wasn't bolted down correctly... as much as I have checked and fixed everything I found that was half-@$$ed put together I am really anxious to see what she does...

 

Sound's likeyou need to advance to timing a little.

 

Well the test drive went pretty good.. started around 0 timing and it basically had no guts... advanced to around 6 and man what a difference... the pick up and power I was looking for (going easy for break-in of course).... it seems as though I could advance even more... I have read before to run it until you hear the valves pinging and then start back down a little... I am running bolt on roller rocker, if that makes a difference...

It didn't go completely smooth however, she's still running a little hot, but holding now (gotta get that 180 t-stat) and after stopping and trying to start hot, my starter took a dump, which I think was killed because now I find my alternator isn't charging... Go figure, the only two parts I didn't replace....

Any suggestions on timing is appreciated...

 

get a timing tape and power time for about 34 degrees total with the vac disconnected and see how it runs.(with the vac reconnected)
http://www.jegs.com/cgi-bin/ncommerc...83&prmenbr=361

 

this sounds like a timing problem to me. improper timing will make your engine overheat for sure. try advancing the timing alittle more.