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Author
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Topic: Blew the head gaskets again!
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BLstangin
Gearhead Posts: 817
From: St. James, MN
Registered: Apr 2002
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posted 07-05-2005 12:09 AM
   
Well today I decided to put my other carb on the 302. Took the 650dp off and put on the proform main body, billet baseplate and billet metering blocks. Took some guesses at jetting and it fired right up and ran great. So I took it out and gave it hell, ran great, twice as good as before and I was impressed with the way it ran before. Then all the sudden there was antifreeze on the road and lots of pressure in the cooling system. It did it before but the coolant got down a ways and it quit doing it, then it started doing it with the coolant down aways so I'm almost possitive it's the head gaskets. So what can I do to get it to stop? This time around I had arp head bolts and the good victor reinz head gaskets. The ones alex recommended. The surfaces should be flat, they were milled and I checked them with a straight edge they were within .001, I just don't get it. I'm thinking maybe some aft 185 heads while its apart, I just don't want it to happen again, What about the lockring head gaskets or whatever, will they work? Its getting sickning, I need a perminent sollution without touching the block if it's possible.------------------
1970 coupe restored with the help of my dad. 306 with 650 dp holley, Weiand Stealth intake, headers, mme custom roller cam, harland sharp roller rockers, kb pistons, 10.3:1 compression ratio, pertonix ignitor 2 with matched coil, lakewood bellhousing, 4-speed toploader, and 3.50 9" locker rear.
1986 f-150, 5.0, factory towing package with original c-6 trans
http://www.supermotors.org/registry/vehicles/detail.php?id=7794
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exlocal
Gearhead Posts: 688
From: hacienda hts., CA, USA
Registered: Dec 2004
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posted 07-05-2005 08:25 AM
Compression check first?Maybe check the intake manifold for straightness before tearing off the heads. ------------------
reliving youth
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pendragon
Journeyman Posts: 9
From: Baytown Tx
Registered: Sep 2004
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posted 07-05-2005 08:39 AM
Do you have the alignment dowels in the block? If you don't the head gasket can slide down and blow out the top of the head gasket. I made that mistake whet I went to studs in my block, I thought I didn't need the dowels anymore. I was wrong.
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70rancheroGT
Journeyman Posts: 25
From: Durham, NC
Registered: Mar 2005
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posted 07-05-2005 12:00 PM
1) What about timing? Your sig doesn't mention the distributor that you are running, but I'm guessing it's a stock unit because of the pertronixs. I went round and round trying to get a stock dizzy to run right and ended up blowing a head gasket due to erratic timing. 2) You said you guessed on jetting the new carb body, what were the jets?I don't know the history of your build, but if the surfaces are true and put together right, then the head gasket shouldn't blow. Unless you have too much timing and/or running too lean and get into detonation problems. Just my two cents,
James
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BLstangin
Gearhead Posts: 817
From: St. James, MN
Registered: Apr 2002
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posted 07-05-2005 01:23 PM
O.k. the build is as follows, 302 .030 over block, line honed, bored and decked. 351W DOOE-C castings with stainless valves, screw in studs, guideplates, and harland sharp roller rockers. Custom hydro roller cam, .550 lift, and 230,[email protected] duration, 110 lsa, crane retrofit roller lifters, weiand stealth intake port matched to heads, which have been ported also. ARP rod, main and head bolts. Heads have been milled .020 and chambers polished also. Carb is a proform main body with a barry grand idle-eze baseplate and quick fuel metering blocks, and my bowls. Powervalves are 2.5 in the front and 4.5 back, and 72 jets both sides. Old carb had same in front but no powervalve and 78 jets in back. Seems to run good, no noticable detonation that I could hear and it runs way stronger, haven't checked the plugs but should be good. Vaccum at idle is about 10" and should probably have a bigger powervalve in the front, but it ran great that way before. Distributor is a stock unit converted with pertronix ignitor 2 msd 6al box with a 6,700 chip, timing is 15 inital and 35 total. Compression ratio is 10.3:1, and I run 92 octane gas. Alignment dowels are in the block and I have the correct washers to locate the bolts to the larger 351w head bolt holes.------------------
1970 coupe restored with the help of my dad. 306 with 650 dp holley, Weiand Stealth intake, headers, mme custom roller cam, harland sharp roller rockers, kb pistons, 10.3:1 compression ratio, pertonix ignitor 2 with matched coil, lakewood bellhousing, 4-speed toploader, and 3.50 9" locker rear.
1986 f-150, 5.0, factory towing package with original c-6 trans
http://www.supermotors.org/registry/vehicles/detail.php?id=7794
[This message has been edited by BLstangin (edited 07-05-2005).]
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70rancheroGT
Journeyman Posts: 25
From: Durham, NC
Registered: Mar 2005
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posted 07-05-2005 05:19 PM
The build sounds great, the only weak point I see is the dizzy. I tried 3 different stock dizzys in my 351C. Two used and one "new" reconditioned one from Autodrone. They all had excessive endplay, especially the "new" one. If you are using the stock unit from your 70 stang, I'm sure your spark is erratic at 6700 rpms. Maybe not the culprit, but a good candidate.
Besides erratic timing, the mechanism for limiting total timing is a pain in a stock dizzy. How did you limit the stock dizzy to 20 degrees of advance? Does it have a 10L slot or did you use a larger bushing in a 13L or 18L? You need to limit total advance by physically limiting the travel, either by welding up the slot or using a larger bushing. If you are limiting the total advance by a heavy spring you may see the correct total at 3000-3500, but at 6500 the spring can't do the job and you end up with too much advance.
I don't mean to keep belaboring the point but I blew a head gasket because of a stock dizzy. I used a piece of rubber vaccuum hose as a bushing to limit total advance, and it wasn't up to the task. I was running at the edge of detonation with 10.7:1 compression and 93 octane. When that rubber bushing disintigrated (at 6500 rpm), head gasket went too.
It seems like you have spent some cash and built a great motor, but you should never skimp on the distributor. It was the last thing I bought, and I wish it was the first. I'll get off of my ignition soapbox now... Maybe there's something else wrong. How old is the radiator cap and what is the pound rating? You haven't mentioned the engine temp, is it getting hot?
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BLstangin
Gearhead Posts: 817
From: St. James, MN
Registered: Apr 2002
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posted 07-05-2005 06:18 PM
My dizzy has a 10L slot in it and that's where it's set. Radiator cap is almost new and is a 13lb stant one. I can't rev it past about 6,300 right now, the valves start to clatter there, I need bigger springs, but I don't think that has anything to do with the head gasket issue. I only rev it to 6,000 or so right now because I don't want it floating valves, but I still think it's somethign else, I just don't know what?------------------
1970 coupe restored with the help of my dad. 306 with 650 dp holley, Weiand Stealth intake, headers, mme custom roller cam, harland sharp roller rockers, kb pistons, 10.3:1 compression ratio, pertonix ignitor 2 with matched coil, lakewood bellhousing, 4-speed toploader, and 3.50 9" locker rear.
1986 f-150, 5.0, factory towing package with original c-6 trans
http://www.supermotors.org/registry/vehicles/detail.php?id=7794
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Bill3888
Journeyman Posts: 52
From: Riverside , Ca
Registered: Aug 2003
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posted 07-06-2005 02:18 AM
I have a 65 289 block (347) using same W heads as you, shaved, big valves ported, solid roller etc- same problem with pressure in the cooling system - Had felpro and changed to the same VR gaskets with no help - I also am at a lose to figure it out - going to try to re-torque mine in the next few days and I plan on going higher on the studs then recommended - If you figure this out please let me know!!
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Capri
Gearhead Posts: 1608
From: Lyons, ILL, USA M&M member #007... the secret agent member
Registered: May 99
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posted 07-07-2005 12:01 AM
#1 is do a cooling system pressure test to see where the coolant is coming from. Whos to say you dont have a cracked head that shows up under pressure?
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BLstangin
Gearhead Posts: 817
From: St. James, MN
Registered: Apr 2002
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posted 07-07-2005 06:46 PM
Because last time I put a pressure tester on it and it would hold it overnight, and when I took it apart it had blown both head gaskets, in a total of 4 cylinders, 2 on each side, and I already know that's what it did, I just don't understand why?------------------
1970 coupe restored with the help of my dad. 306 with 650 dp holley, Weiand Stealth intake, headers, mme custom roller cam, harland sharp roller rockers, kb pistons, 10.3:1 compression ratio, pertonix ignitor 2 with matched coil, lakewood bellhousing, 4-speed toploader, and 3.50 9" locker rear.
1986 f-150, 5.0, factory towing package with original c-6 trans
http://www.supermotors.org/registry/vehicles/detail.php?id=7794
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Moneymaker
Administrator Posts: 26813
From: Lyons, IL, USA
Registered: May 99
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posted 07-07-2005 06:52 PM
I'll believe it when you pull the heads off.------------------
Alex Denysenko
Co-Administrator and Moderator NHRA/IHRA/SRA member and licensed Superstock driver
NHRA and IHRA SS/LA & SS/MA National Record Holder '00,'01,'02,'03,'04 &'05
First NHRA & IHRA 289 automatic Superstock Mustang in the TENS 06-99
First SS/MA in the TENS 04-03
IHRA division 5 Superstock Champion
Fleet of FoMoCo products including 88 ASC McLaren Mustang #28 The Barry of BarrysGrrl Quote #1: "I never met a magazine mechanic I liked."
Quote #2: "Make sure brain is in gear before engaging mouth!"
Quote #3: "If you can't run with the big dogs, stay on the porch!"
www.moneymakerracing.com
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Capri
Gearhead Posts: 1608
From: Lyons, ILL, USA M&M member #007... the secret agent member
Registered: May 99
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posted 07-07-2005 07:12 PM
Same here.If it has 4 holes blown, I want to see pictures of the gaskets.
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Fordwiser
Gearhead Posts: 429
From: Metamora, Illinois
Registered: Dec 2000
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posted 07-07-2005 07:57 PM
Where was the antifreeze coming from, the overflow, the exhaust, between the head and block? Anything in the oil? My first guess would be the thermostat isn't opening all the way or is sticking. Easy to check with a pan of water on the stove and a thermometer. I would do a lot of checking and eliminating possibilities before I pulled the heads.Roger
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BLstangin
Gearhead Posts: 817
From: St. James, MN
Registered: Apr 2002
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posted 07-09-2005 12:49 AM
O.k. I decided to go look at it again today. The oil had a little white streak on it on the dipstick and then I took the breather out and the pcv vavle out and they had little green spots on them and a couple of white streaks so it's definitely got water in the oil. Anyway, I think I'll be putting afr 185 heads on it while it's apart, and maybe lockring it. we think maybe it's pinging at higher rpm and we can't hear it. Do you guys think that the lockring will solve the problem? Thinking maybe I should go from the arp head bolts to studs? Also the last time it blew the gaskets it blew both gaskets 2 cylinders on each side, I haven't taken it apart yet to see what it looks like this time. ------------------
1970 coupe restored with the help of my dad. 306 with 650 dp holley, Weiand Stealth intake, headers, mme custom roller cam, harland sharp roller rockers, kb pistons, 10.3:1 compression ratio, pertonix ignitor 2 with matched coil, lakewood bellhousing, 4-speed toploader, and 3.50 9" locker rear.
1986 f-150, 5.0, factory towing package with original c-6 trans
http://www.supermotors.org/registry/vehicles/detail.php?id=7794
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Capri
Gearhead Posts: 1608
From: Lyons, ILL, USA M&M member #007... the secret agent member
Registered: May 99
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posted 07-09-2005 11:55 AM
What Id be intrested in knowing is what the heads were torqued to and in what sequence. Unless the block/heads are cracked or warped there is no reason they should be popping head gaskets. Especially the Victor gasket. The pressure test will help tell what is going on.
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BLstangin
Gearhead Posts: 817
From: St. James, MN
Registered: Apr 2002
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posted 07-09-2005 02:15 PM
First time all by the book. The second time with the victor gaskets, I went with arp head bolts and went 65ft/lbs on the bottom and top with the arp moly lube, then went back to the top and torqued them to 75 ft/lbs and then checked that the bottom ones were still at 65. They were torqued in the proper order also. Center two, then to 2 to the left, then 2 to the right of the center to, back to the back ones on the left, then back to the right again. Looking at it from the exhaust port side.------------------
1970 coupe restored with the help of my dad. 306 with 650 dp holley, Weiand Stealth intake, headers, mme custom roller cam, harland sharp roller rockers, kb pistons, 10.3:1 compression ratio, pertonix ignitor 2 with matched coil, lakewood bellhousing, 4-speed toploader, and 3.50 9" locker rear.
1986 f-150, 5.0, factory towing package with original c-6 trans
http://www.supermotors.org/registry/vehicles/detail.php?id=7794
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