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P400 in the Burb install

If the head studs were not already installed with UltraBlack RTV I would pull a head and redo the valve to piston clearance with clay again and solid lifters and my pushrod checkers set at zero lash. But I think I'm good, what do you think Chris? Chris are both the valve reliefs cut to the same depth? I never checked.
 
A simple way is a valve drop @ TDC, much easier, a dial indicator on the top of a valve with no spring and measure the drop...

And yes the reliefs are the same depth..
 
A simple way is a valve drop @ TDC, much easier, a dial indicator on the top of a valve with no spring and measure the drop...

And yes the reliefs are the same depth..
But this way would not account for any cam or valve train geometry, correct?

Here's some info....https://www.kelfordcams.com/global/technical-advice/checking-piston-to-valve-clearance/
 
Better check the cam specs . I had to play with mine when I put the other cam in .
 
Ok Chris, I dropped a valve on the #1 piston and used it to make sure it was on TDC with my dial indicator, and then measured the valve drop on both valves and I got .145" on the intake and .135" on the exhaust. Would you mind sharing how to do the math to figure out the valve to piston clearance? I think you know the cam specs and that I'm using 1.7:1 rockers, with a gear drive on the cam. Thx in advance.
 
Dave, I mostly use a degree wheel and don't button the heads down till I'm sure things are the way I want them, I have seen stock cams that needed to be advanced or retarded with keys and very few are where they should be in stock form.. Your drop numbers are a bit more than mine, but you used a thicker gasket than I do.. so that gives more clearance's than what I see as well... your good and no chance of touching... once my numbers on the wheel match the specs I have next is plenty of putty on the piston and several turns on the crank, I use feeler gauges to match my gasket thickness and I check 4 holes not just one... over kill maybe but once I bolt the head & gasket down I don't worry... the marks on the gear drive aren't correct either, I never trust just the marks.. for instance the stock cam in my motor is advanced 4* wit a key, and per the specs it's only 1* advanced per spec sheet... I'm not going to use the stock cam but I wanted to check the gear drive, it's all coming back out when the new cam gets made...
 
@spdgofast , for reference a few measurements below...

My piston valve pockets - .050" deep
Stock P400 head valve recess - .035" average
Stock block piston protrusion - .005" average
Head gasket thickness - ?
At the cam valve lift - .280"

So with some figuring a true clearance can be found...

I have found the stock in use piston to valve clearance varies, some motors show signs of touching, others don't, hence the putty test is important on all 4 corners I think...
 
Hey guys, what's the best thermostats to use in the dual thermostat set up? I just took my thermo assembly apart today to send off to the powder coater and found one of mine had fallen apart. I'm pretty sure I got these from the GM dealer, installed 120 miles ago, when the new P400 was installed.
 
Well guys, I finally got the motor in the truck and fired it up without a turbo or intake manifold. Initially I lined up the timing marks on the IP and the gear cover case but I had to advance it quite a bit, (like 3/16 of an inch between the timing lines to the advanced side). When I checked it with the timing light its at 6* BTDC, I think it's going to want more timing advance, I'm guessing this is because of the lower 18:1 compression ratio? I hope to be able to button it up and drive it by next weekend, we'll see.
 
Well I finally had some time to post up about my build today so here's the latest. So I had to advance the pump as for as I possibly could meaning the mounting bolts and the adjustment slots in the pump where turned as for to the advanced side as I could get it and it still wouldn't run very well and when I put the timing light on it it was still @ about 6* BTDC. So I put my spare stock .310 pump on it and it runs like I would expect it to run. So just so you know the first pump that doesn't run right is the second pump that I had Conastoga Diesel build for me, the first pump they built for me seized the head & rotor at idle. Neither of the two Conastoga pumps have ever made it to the point of running with the truck in gear so I'm done sending them my business. So Chris had told me about Classic Diesel Designs and I have been trying to get ahold of them since last friday regarding building me a pump but I have not gotten a response back from them. I've tried messaging them through the contact tab on their website, direct email and through their Facebook page, I've been unable to find a phone number for them so if anyone has a phone number for them please share it with me. It is quite frustrating to have spent the time and $ that I have on this truck and I can't find anyone who can build an injection pump for it.
 
Thats weird, Wes from CDD usually responds to any messages I've sent him within a few hours. Stanadyne still sells completely new updated DB2s for $1400. Any stanadyne distributor should be able to order one for you.
 
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Thats weird, Wes from CDD usually responds to any messages I've sent him within a few hours. Stanadyne still sells completely new updated DB2s for $1400. Any stanadyne distributor should be able to order one for you.
I'm not looking for a regular stock DB2.
May I ask what method do you usually use to contact him?
 
I'm not looking for a regular stock DB2.
May I ask what method do you usually use to contact him?

Facebook messenger. You can still get the .330 marine pump new. But if your after more fuel then a custom pump is definitely what you need. CDD locks timing on his pumps so if you get one you will lose your dynamic timing just so you know.
 
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