95ttoplt1 Posted November 21, 2011 Report Posted November 21, 2011 Hey guys just milled my head and got it back on. It was warped pretty bad (.018) but they took .070 off it. Well my daughter and I got it all torqued down, put the plugs back and went to fire it up, nothing... Pulled the plugs and they were all mashed closed Did I miss the memo about running a certain plug after milling the head? Quote
55 Fargo Posted November 21, 2011 Report Posted November 21, 2011 Hey guys just milled my head and got it back on. It was warped pretty bad (.018) but they took .070 off it. Well my daughter and I got it all torqued down, put the plugs back and went to fire it up, nothing... Pulled the plugs and they were all mashed closed Did I miss the memo about running a certain plug after milling the head? Hell no, they done scalped this sucker, instead of a moderate shave, .030 would have been plenty. Sorry to hear this has happened... Quote
95ttoplt1 Posted November 21, 2011 Author Report Posted November 21, 2011 Hell no, they done scalped this sucker, instead of a moderate shave, .030 would have been plenty. Sorry to hear this has happened... .070 was what was recomended to get the compression up to 8:1 Quote
greg g Posted November 21, 2011 Report Posted November 21, 2011 Well suposedly you can take .090 off a stock head. But if it had already been clut or the deck blocked, who can know. Its the valves that would contact the plugs, what plugs are you running?? Quote
Jerry Roberts Posted November 21, 2011 Report Posted November 21, 2011 I guess that you put in the same plugs that you removed and not some new ones that are too long . The head could have been shaved some in the past too . I saw a used head on ebay yesterday . Vintage Power Wagons sells new heads at a reasonable price . Quote
95ttoplt1 Posted November 21, 2011 Author Report Posted November 21, 2011 (edited) Well suposedly you can take .090 off a stock head. But if it had already been clut or the deck blocked, who can know. Its the valves that would contact the plugs, what plugs are you running?? Champion J12YC, They clear with two gaskets. But out of curiosity I got out my compression tester, I had 90 psi with oil before I pulled the head. The truck has been sitting since 1975 so it was expected to be a little low till we get it running and get things broke loose again. Well now I have 180psi with oil!! WTH? Did the dude fall asleep at the mill?? Soo beer math off this chart shows I now have a 10:1 flathead, awesome..... Edited November 21, 2011 by 95ttoplt1 Quote
greg g Posted November 21, 2011 Report Posted November 21, 2011 Why the 12's? J 8 are the recommended, or AC 45, which are not projected tips. The 12 are 4 heat ranges hotter and have an extended tip. Quote
95ttoplt1 Posted November 21, 2011 Author Report Posted November 21, 2011 Why the 12's? J 8 are the recommended, or AC 45, which are not projected tips. The 12 are 4 heat ranges hotter and have an extended tip. Crap, mine had AC 4s in it when I got it. And they crossed to the ones I have now. I'll take these numbers with me tomorrow and see what I can get. Quote
james curl Posted November 21, 2011 Report Posted November 21, 2011 We took .100 of of my head and .010 off of the top of the block. I had to decrease the radii over the valves to prevent them from striking the head in the radii above the valves. I have about 30,000 miles on this setup with out any problems. The AC 45 plugs are what I use and have never had a problem. Quote
95ttoplt1 Posted November 21, 2011 Author Report Posted November 21, 2011 We took .100 of of my head and .010 off of the top of the block. I had to decrease the radii over the valves to prevent them from striking the head in the radii above the valves. I have about 30,000 miles on this setup with out any problems. The AC 45 plugs are what I use and have never had a problem. Thanks James! I got a set of AC 45's on the way to work today, they are way differnet than what I was running. What is your cranking compression? Quote
95ttoplt1 Posted November 21, 2011 Author Report Posted November 21, 2011 It is the PISTONS that struck the plugs, your valves are off to the side on a flathead. The spark plug sits directly over the intake valve on a 218. Quote
Phil Martin Posted November 21, 2011 Report Posted November 21, 2011 I put a plug that was too long in 218 onetime and bent the valve under it. They are over a valve not a piston. Quote
JIPJOBXX Posted November 21, 2011 Report Posted November 21, 2011 I had my head milled about .060" and had no problems- You might be able to take two spark plug gasket and bring up the plug? Well good luck! Jon Quote
Don Coatney Posted November 21, 2011 Report Posted November 21, 2011 (edited) How much oil did you dump into the cylinders when you did your compression check? Too much oil will give a false reading at the oil makes the displacement smaller. The tips on your hot plugs should not extend further into the cylinder than the cold plugs. Below is some information on hot plugs verses cold plugs. Also are you running a stock camshaft? When I installed my re-ground camshaft I used a dial indicator to measure the lift and to insure I would not have a clearance issue. Edited November 21, 2011 by Don Coatney Quote
Don Coatney Posted November 21, 2011 Report Posted November 21, 2011 It is the PISTONS that struck the plugs, your valves are off to the side on a flathead. Mark; The spark plugs are directly above the intake valve not above the piston. Quote
greg g Posted November 21, 2011 Report Posted November 21, 2011 The Champion plug chart says the 12's have a projector tip and the 8's do not. Quote
Don Coatney Posted November 21, 2011 Report Posted November 21, 2011 The Champion plug chart says the 12's have a projector tip and the 8's do not. Does that "projector" tip actually project further into the cylinder or further from the ceramic as pictured above? Quote
kencombs Posted November 21, 2011 Report Posted November 21, 2011 I'm going to start on mu 230 this winter. I have a spare head from a previously rebuilt forklift engine. There have been past discussions here regarding the stock thickness of the head. But, I couldn't fine a definitive answer. I would like to be able to measure the head and determine if it has been milled in the past. Any info out there??? Quote
greg g Posted November 21, 2011 Report Posted November 21, 2011 Don that is what I am inclined to think but with out a plug or picture, cant be sure. Quote
T120 Posted November 21, 2011 Report Posted November 21, 2011 ..Just so happens.Did a rough measurement - 3mm longer Quote
Don Coatney Posted November 21, 2011 Report Posted November 21, 2011 ..Just so happens.Did a rough measurement - 3mm longer[ATTACH]31240[/ATTACH] Excellent! That is the answer. Thanks for posting! Quote
greg g Posted November 21, 2011 Report Posted November 21, 2011 All it takes as a couple silly millimeters. Quote
Dodgeb4ya Posted November 22, 2011 Report Posted November 22, 2011 Whats this metric stuff with our old MoPars. None of my shop manuals for my cars show metric info! I guess I need to raise my Bonnet to measure my sparking plugs. Quote
95ttoplt1 Posted November 22, 2011 Author Report Posted November 22, 2011 How much oil did you dump into the cylinders when you did your compression check? Too much oil will give a false reading at the oil makes the displacement smaller.The tips on your hot plugs should not extend further into the cylinder than the cold plugs. Also are you running a stock camshaft? When I installed my re-ground camshaft I used a dial indicator to measure the lift and to insure I would not have a clearance issue. I think I may have gotten a little more oil than I needed, I was thinking about that last night. I'm not too worried for now, I'll run it and let everything lossen back up and then do another test and see where its at. The front two cylinders were at about 90, I gave them maybe two squirts of oil and they came up to about 120, which was what I was expecting. I kept going and about #4 it didnt seem to respond to the oil, so I gave it two or three more squirts and it jumped to 180. Shocked I started testing the others and the ones that were previously 120 were at 180 now. Not sure but maybe the oil ran off the deck into the cylinders? The plugs I picked up today are noticably shorter than what I had installed and look like they will clear. Someone must have put the hotter plugs in long ago and since the head was stock(hopefully) they never hit. Cam is stock. Quote
Don Coatney Posted November 22, 2011 Report Posted November 22, 2011 Whats this metric stuff with our old MoPars. None of my shop manuals for my cars show metric info! I guess I need to raise my Bonnet to measure my sparking plugs. There are 6 applications for metric threads on all old mopars flatheads. I believe the measurement fits the bill. Quote
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