Engine/Transmission (1994 - 1998) Help!! machine shop botched fire ring job

[LVJUNIOR]

I blew my brand new head gasket. I just got finished measuring the fire ring grooves the machine shop cut in my head. I pulled out the instructions that came with the fire ring gasket set that I gave to the machine shop. The spec called for 4. 508" O. D. +/- 0. 001" the closest they got was 4. 529" and the farthest they were off was 4. 599". Are you kidding me? with a tolerance of one thousandths they were off almost a full tenth. The fire ring is only . 105" thick. The groves are supposed to be . 120" wide and they varied from 0. 115" to 0. 126" #@$%!



Now to see if I can find a way to salvage my brand new ported head. Given that I dont have any consistency in grove size and vary from 4. 529" to 4. 599" what can I do to make this head usable.

 

[Missouri Mule]

I try to have the machine shop replace the head they are the ones that made the mistake.

 

[LVJUNIOR]

I am going to the machine shop tomorrow. It is a Brazilian casting and I really don't wan't to get a chiniese casting if I don't have to. Besides this head was ported by Joe Donnely so I know it's done right. I would like to save this one if possible

 

[JDKammin]

Call Midwest Cylinder Head in Nevada, IA. The phone number is 800-873-8506. They do all kinds of head and block repair. They can weld up your grooves, re-surface the head flat and re-machine the grooves correctly. I have my head off for firerings and will be taking my head to Midwest Cylinder.

 

[charlessmith]

Sorry to hear that this is the cause! I was looking forward to hearing you'd solved your low boost fuel situation ...
Charlie

 

[LVJUNIOR]

I think it was having a hard time lighting the antifreeze in the cylinders until it got some rpm. I bet once I get the head gasket right I find my bottom end power.

 

[LVJUNIOR]

The machine shop wants to send the head off and have the grooves nickel welded and start over. Anyone ever seen This done with fire rings. If so what kind of success. Can you still get a new Brazilian casting?

 

[KEdenfield]

How do you weld cast iron without cracking it? Even if the guy has enough skill to not crack it while welding, it would cause to many stress risers for crack initiation followed by propagation. May work on a gas motor. Don't trust it on a diesel.



Just have the grooves cut all uniform and get custom sized fire rings made. I'd pay for custom laser cut rings from sheet stock before I let anyone weld on an iron head I wanted to salvage.

 

[fest3er]

I think it was having a hard time lighting the antifreeze in the cylinders until it got some rpm. I bet once I get the head gasket right I find my bottom end power.

TDR is all about edjamucation, and here's a great opportunity.



There seems to have been some misunderstanding here. One is supposed to put fuel in the fuel tank and antifreeze in the radiator tank. The engine just won't work well with 'em t'other way 'round.



I hope you get your head straightened out. Seriously. As to welding cast iron, I understand it is done with great care and more than lots of patience.

 

[CumminsPower98]

How do you weld cast iron without cracking it? Even if the guy has enough skill to not crack it while welding, it would cause to many stress risers for crack initiation followed by propagation. May work on a gas motor. Don't trust it on a diesel.

Just have the grooves cut all uniform and get custom sized fire rings made. I'd pay for custom laser cut rings from sheet stock before I let anyone weld on an iron head I wanted to salvage.

As far as I know they heat the whole piece up in an oven and may even weld it while its in the oven but not sure on that last part. The heat will keep it from cracking as well as relieve stresses. Years ago I rebuilt a John Deere 3020 Diesel and the head had really bad rust craters in one or more cylinders so it was welded up and surfaced. and it ran great for years and as far as I know its still going and that was 16 years ago.

 

[WDixon27]

lotsa heat and a day or so cooling down, i just did a exhaust manifold for a turbo project and got it to around 900 on a propane burner then after welding massaged it with a hammer and covered it with a piece of metal and lowered the burner every few minutes till it was off and let it cool in still air, your job is not this easy and needs a pro who advertises this type of work

 

[LVJUNIOR]

After talking to Van at Haisley Machine I am down to two options. option A shave the heads and the valve seats . 030 removing the bad groves and adding new grooves and thicker injector washers. Option B used brazilian casting with porting to match mine and new grooves. I am leaning towards shaving the head since it only has 500 miles on it. any thoughts?

 

[budnate]

I would ask this question to a diesel guru, on a gas motor you have to pay close attention to Quench if you want a good running motor.



the quickie explanation is this is the volume in the combustion chamber when the piston is at TDC and the valves closed, this sets your compression ratio. to tight and you cant run on pump gas and possible valve clearance issues, to loose and you have a slug motor.



I never hear anyone talk about it with diesels?..... so when is to much compression come into play for a street motor?



I would run your motor around by hand and measure where the pistons are in relation to your block deck height and flip your head over and CC your head and see roughly where your at before taking . 030 off.

 

[Bob4x4]

I would ask this question to a diesel guru, on a gas motor you have to pay close attention to Quench if you want a good running motor.



the quickie explanation is this is the volume in the combustion chamber when the piston is at TDC and the valves closed, this sets your compression ratio. to tight and you cant run on pump gas and possible valve clearance issues, to loose and you have a slug motor.



I never hear anyone talk about it with diesels?..... so when is to much compression come into play for a street motor?



I would run your motor around by hand and measure where the pistons are in relation to your block deck height and flip your head over and CC your head and see roughly where your at before taking . 030 off.

:-laf Our head does not have a chamber

 

[LVJUNIOR]

I have been trying to explain the lack of combustion chamber to my friend for three days to no avail.

 

[Bob4x4]

Simple... ... ... . the piston top is the chamber and the head is flat if he doesn't picture that... ... ... ... ... ..... give up on him :-laf

 

[fest3er]

I have been trying to explain the lack of combustion chamber to my friend for three days to no avail.

A rough calculation is that the piston is about . 2" from the head at TDC, maybe even closer, depending on the volume of the bowl in the piston. The piston could well nearly touch the head if the bowl is big enough.



To drop compression from 17. 5:1 to 15:1 requires a head gasket that is about . 05" thicker.

 

[budnate]

DOH!, I assumed there was a pocket for the injector to hang out in, post up some pics for a newbie diesel guy.



so a typical motor is set with it being . 02 down the hole? , thats pretty tight on a zero clearance head, is that a typical clearance on all of these when new or rebuilt?



peace, B.

 

[SMorneau]

First, Aren't fire-ring grooves cut in both the block and head? Is the block grooved correctly?

Second, call Diesel Cast Welding in Blaine Minnesota. They can sell you a new loaded head for well under a $1000 and they can also tell you how it is possible to fix the old one. They do blocks and heads for almost every diesel and you can find them online.

I have heard thru a friend that the new heads they sell are very nice. Larger bosses, some other improvements and reportedly a guy who ports them says the metal composition is very good quality.

If you are going to look for a used 12 valve head I am told the ones cast by navistar are higher in nickel content. Ithink they have a casting mark that on either the top or bottom of the intake, I forget where exactly. Someone else can probably elaborate on this.

Good luck,
Scott

 

[MMeier]

So Junior, who screwed up the job in the first place ???