I Harp & Harp But It Happened Again!!

John Saeli

Well-known Member
When we provide a Diesel Engine Kit, I always lecture the customer to NOT let anyone Grind Valves & Seats. I tell them "If the man at the machine shop says he will grind the valves & seats, then pick the heads up off the counter and get out of there, because he does not know what he is doing. The principle is the same for any diesel.
When you grind valves and seats, the valves are recessed into the head, opening up the combustion chamber area, lowering compression. CASE says that for every .005" valve recession, you lose .1 in compression. That's per valve!!
2 months ago we provided a kit for a 188 Diesel. A month later the customer called back complaining the engine wouldn't start, just smoke. We go through everything over the phone. I asked about the valves but didn't get an answer only he took it to the best shop in 3 states. Heard that before. He pulls the head and gets back, and the valves are way sunk it. This is the 4th time in 12 years that this has happened. When I ask, "Didn't you hear my lecture?" "Yes, but the man at the shop said you was full of $hit." We have another customer who's shop says I'm "full of $hit". This customer has a '70 Series Diesel and he is very satisfied with his tractor because he doesn't have to use the manifold heater until it gets below 50F.
The 188 customer got his head back, done right this time, and he called to tell me she starts excellent.
When you spend all that $$$ on the lower end, wouldn't you want the valves right? ACG (Loren) used to say he wants the valves to "Stand Proud". How right he was!! Our 730 & 800 will start @ 40F in 5 seconds, no heat. Our 630 and the rest of them here will start @ 25F or colder in 5 seconds. Good batteries are a must.
 
The last five diesel heads I've had off needed ALL valve seats replaced due to borderline valve location. My favorite common complaint is the Oliver/Wakesha 283/310 diesels, those heads when new have all the valves .040/.050 OUT of the deck as the short stroke engine has trouble building compression heat anyway. Pistons have valve reliefs cut in the tops also for valve clearance. Just recently a customer I serviced his pump and injectors for his Oliver 1655/283 complained about hard starting cold after engine had all new sleeves/pistons installed. I asked about the head, all valves and seats were reground and used as is, said the valves were SLIGHTLY below the head deck. He didn't want to hear it when I said get the head off and done RIGHT, and then it will start cold. Diesels will run OK with 300 PSI once started but don't start well that low cold. 375/425 PSI is what I like to see for best cold starting.
 
When we provide a Diesel Engine Kit, I always lecture the customer to NOT let anyone Grind Valves & Seats. I tell them "If the man at the machine shop says he will grind the valves & seats, then pick the heads up off the counter and get out of there, because he does not know what he is doing. The principle is the same for any diesel.
When you grind valves and seats, the valves are recessed into the head, opening up the combustion chamber area, lowering compression. CASE says that for every .005" valve recession, you lose .1 in compression. That's per valve!!
2 months ago we provided a kit for a 188 Diesel. A month later the customer called back complaining the engine wouldn't start, just smoke. We go through everything over the phone. I asked about the valves but didn't get an answer only he took it to the best shop in 3 states. Heard that before. He pulls the head and gets back, and the valves are way sunk it. This is the 4th time in 12 years that this has happened. When I ask, "Didn't you hear my lecture?" "Yes, but the man at the shop said you was full of $hit." We have another customer who's shop says I'm "full of $hit". This customer has a '70 Series Diesel and he is very satisfied with his tractor because he doesn't have to use the manifold heater until it gets below 50F.
The 188 customer got his head back, done right this time, and he called to tell me she starts excellent.
When you spend all that $$$ on the lower end, wouldn't you want the valves right? ACG (Loren) used to say he wants the valves to "Stand Proud". How right he was!! Our 730 & 800 will start @ 40F in 5 seconds, no heat. Our 630 and the rest of them here will start @ 25F or colder in 5 seconds. Good batteries are a must.
You probably don't have the time to waste that I do. I have no TV so I watch you tube. JAMSI is a great channel. Unfortunately they're on the other end of the country!
 
I have had 3 30 series engines done, and my head guy argues every time. The one I insisted have the intake valves flush is the 301 I put in my 400 and it will start with nothing down to at least 30 deg. My 830 he couldn't quite get them to flush, I think they are down a couple thousandths, it will start down almost to 30 deg. The 1030 is the worst because I let him talk me into .005 recess. It won't start at 40 without help.
 
so basically there is no sense to grind the valves and seats then. just from hrs put on the valves the seats wear a seat pattern in them and to get them smooth again you would be over the limit. just order new stuff , is what you are saying. saying once you have a seat width as wide as the valve face your done. a general seat width was 1/16 for intake and 1/8 for exhaust valves.
 
It is more the fact that the shop doing the head work is not properly educated on the finished product requirements. This means valve height that meets proper specifications after grinding, reseating or whatever you want to call restoring the surfaces of the valves and seats for proper sealing.
 
It is more the fact that the shop doing the head work is not properly educated on the finished product requirements. This means valve height that meets proper specifications after grinding, reseating or whatever you want to call restoring the surfaces of the valves and seats for proper sealing.
that would be resurfacing the valves, even new valves are put on the grinder and given a light resurfacing. there have been times when the valve face gets damaged and if not checked properly you have a problem. them old ford 352 and 390 and 428 engines you had to make sure all valves where at the same height when done your valve grind. it was called installed valve height. all you did was tighten the rocker shaft down and that was your valve adjustment. plus remember the valve springs were checked for pressure also.
 
You know I can't resist this topic!
Had my 188D rebuilt with a reground cam (.262 lobe lift), new lifters, push rods, rockers, shafts, valves and seats. Block was decked .0035, upgraded to wide-flange sleeves, protrusion .003.
I asked for flush but no valve protrusion fearing valve-to-piston clearance. They had to find special deep seats to make it work. Worst cylinder ended up .004 recession intake and .003 recession exhaust. Stock compression is 17.5:1 and by my math I came up with about 17.66:1 for the new cylinder. Decking the block more than made up for the valve recession.
Turned out to be .050 valve-to-piston clearance at zero lash so that was quite comfortable but things were so tight, I was barely able to get the final .014 lash on one valve with rocker adjusting screw all the way in.
She doesn't pop off like some of your engines John but I don't mind getting a little oil moving before it fires anyway.
Just out of curiosity, where does everyone set their throttle to start??
 
Well it better be working correctly Dieseltech, you rebuilt it, lol!
I've been going with 1/2 throttle and even pumping it back to idle so maybe I'm flooding it...
 
Well it better be working correctly Dieseltech, you rebuilt it, lol!
I've been going with 1/2 throttle and even pumping it back to idle so maybe I'm flooding it...
Some diesels like to be cranked 4/5 seconds with the fuel stop OFF, to build some cylinder heat, then while still cranking turn fuel stop ON to start engine.
 
You know I can't resist this topic!
Had my 188D rebuilt with a reground cam (.262 lobe lift), new lifters, push rods, rockers, shafts, valves and seats. Block was decked .0035, upgraded to wide-flange sleeves, protrusion .003.
I asked for flush but no valve protrusion fearing valve-to-piston clearance. They had to find special deep seats to make it work. Worst cylinder ended up .004 recession intake and .003 recession exhaust. Stock compression is 17.5:1 and by my math I came up with about 17.66:1 for the new cylinder. Decking the block more than made up for the valve recession.
Turned out to be .050 valve-to-piston clearance at zero lash so that was quite comfortable but things were so tight, I was barely able to get the final .014 lash on one valve with rocker adjusting screw all the way in.
She doesn't pop off like some of your engines John but I don't mind getting a little oil moving before it fires anyway.
Just out of curiosity, where does everyone set their throttle to start??
Optimum protrusion on your engine head is .005", so if your not there on any valve, you don't have 17.66 on any cylinder. 60 years ago I was taught to open the throttle wide open on cold cranking, and of course as soon as she starts , cut back to an idle.
 
Optimum protrusion on your engine head is .005", so if your not there on any valve, you don't have 17.66 on any cylinder. 60 years ago I was taught to open the throttle wide open on cold cranking, and of course as soon as she starts , cut back to an idle.
Yes, .005 valve protrusion would have worked for me but noone wanted to pre-assemble the engine just to check valve-to-piston clearance first, so I wanted to play it safe. I'm not sure they had enough valve seat to do it either.
Decking the block .0035 should have made up for the valves unless the pistons come up that far above the block. In that case, I lose.
Seems to me I used to start 'em that way too, but it wasn't quite 60 years ago!
 
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that would be resurfacing the valves, even new valves are put on the grinder and given a light resurfacing. there have been times when the valve face gets damaged and if not checked properly you have a problem. them old ford 352 and 390 and 428 engines you had to make sure all valves where at the same height when done your valve grind. it was called installed valve height. all you did was tighten the rocker shaft down and that was your valve adjustment. plus remember the valve springs were checked for pressure also.
That series Ford engines with non-adjustable rockers had hydraulic lifters that self adjusted.The ones with solid lifters had adjustable rockers [which I learned to adjust with the engine running].yes it was messy.My 390 was a Police Special cast iron headers and decent cam in a '64 Galaxy fast back .
 
That series Ford engines with non-adjustable rockers had hydraulic lifters that self adjusted.The ones with solid lifters had adjustable rockers [which I learned to adjust with the engine running].yes it was messy.My 390 was a Police Special cast iron headers and decent cam in a '64 Galaxy fast back .
Yes. I adjusted many GM lifters running also, but they were hyd. So it was way easier. I prefer to do the solid lifters not running. Way more accurate
 
That series Ford engines with non-adjustable rockers had hydraulic lifters that self adjusted.The ones with solid lifters had adjustable rockers [which I learned to adjust with the engine running].yes it was messy.My 390 was a Police Special cast iron headers and decent cam in a '64 Galaxy fast back .


Love those '64 Fords.

I'm picturing yours in black with red interior, buckets, a 4 speed and big meats on Cragars.

Am I close?
 

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