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65 classic 660 lead fuel additive questions
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vinny View Drop Down
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Points: 2837 		Post Options Post Options   Thanks (0) Thanks(0)   Quote vinny Quote  Post ReplyReply Direct Link To This Post Posted: Dec/02/2016 at 10:08am
You might be able to seal that cracked intake with some screen and JB Weld provided it doesn't get affected by the heat of the exhaust manifold. That could buy you some time until a sound manifold presents itself, which it surely will.

It could be too that one or more valves or rockers are sticking. The early engines had oiling problems to the rocker shaft which will show if you are not getting oil to the front rockers. There is a fix for that.
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Points: 196 		Post Options Post Options   Thanks (0) Thanks(0)   Quote 65Classy Quote  Post ReplyReply Direct Link To This Post Posted: Dec/03/2016 at 4:30am
Yeah I've looked into the oiling fix I cleaned it all up its possible it wasnt getting oiled properly I had alot of tapping noise in the front when I had it running. I finally got it home and I'll be digging into it later today. I was talking with a friend and he has a couple parts jeeps I can rob parts from so I've looked around for info on the 4.0 head swap and i can't find a definitive answer to wether their compatible and what all if I'd need if it would work at all I'd love to upgrade to fuel injection to modernize as I want to drive it alot and for long distances.
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Originally posted by farna farna wrote:

The lead additive hype is a myth. Lead does help lube the valves, but not having it only has a marginal effect on wear... about 10-15% more. So if you went 100K before a valve job, you'd only go 85-90K without leaded gas. Engines that are run hard, such as race cars and heavy trucks, wear a bit more.

You can get a new manifold, or at least a good used one. Shouldn't be too hard to find, was used from late 64 to early 1980.  Now I'm not sure all will interchange across those years, but they will for sure if you get the intake with the exhaust manifold. You can even use a late 80-89 aluminum intake with the matching cast iron exhaust manifold.

The cracked intake might be the cause of the backfire, and it could have caused a burnt valve.

If it makes you feel better you can have the head rebuilt with valve seat inserts in the exhaust valves (they wear fastest), or both valves. That's not your problem -- though you could still have a burnt valve.
I agree 100%..Lead helps but not needed...
68 AMX 390 4 Speed,68 American,64 American 2 Door Wagon Altered Wheelbase,78 Concord Build 360,727,8.8
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Points: 7555 		Post Options Post Options   Thanks (0) Thanks(0)   Quote tomj Quote  Post ReplyReply Direct Link To This Post Posted: Dec/03/2016 at 9:09pm
the 232/258 series seems quite fine without the lead. funny this thread popped up again, as i just heard from my engine builder, Pete Fleming, now tearing into my warmed-over 195.6 OHV. in that engine, i used the same regimen that was so soccessful on my old 232 -- dino oil plus zddp additive for breakin, two generously early oil changes, then immediate switch to Mobil1, 15W-50. on the 232, i personally put 350,000 on one overhaul (plus one additional valve job).

on my 195.6 OHV, however, there is fairly serious cam follower damage. scuffing between cam lobe and follower. no oil delivery problem, oil did not break down (my and builders evaluation, plus i sent it to Blackstone before and after my rally). Fleming's opinion is that its the cam and lifter design, the 232/258 is modern and superior here.

so i will be running dino oil plus ZDDP in the 195.6 OHV when i get it back, and not synthetic. even though hen i called Mobil 1 on the phone, they said that 15W-50 specifically has zinc for older engines.

i did run this engine fairly hard, 40,000 - 50,000 miles, and i august this year, burned up the conn rod bearings. Pete's gonna measure the clearances, we suspect it was tight, and this engine has a bottom-end heating problem which i hope to solve with a huge-a** oil cooler.
1960 Rambler Super two-door wagon, OHV auto
1961 Roadster American, 195.6 OHV, T5
http://www.ramblerLore.com
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Points: 16614 		Post Options Post Options   Thanks (0) Thanks(0)   Quote purple72Gremlin Quote  Post ReplyReply Direct Link To This Post Posted: Dec/04/2016 at 7:58am
Pretty much for older engines, lead is helpful but for 99% of them, not really needed.   Ive seen old cars running and they are running unleaded.    when the valve guides and valves are worn, a valve job will not last and is a waste of time.  but I do not believe lead is that helpful.
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Originally posted by FSJunkie FSJunkie wrote:



Engines designed for unleaded fuel have hardened exhaust seats that more closely match the hardness of the valve. This greatly reduces micro-welding and wear from the valve. Hardened exhaust seats started in 1975.

Not so.   part numbers are the same for the pre 74 engines.  the catalytic converter came out in 1975. 



My 232 wore out its exhaust seats in only 15,000 miles because the valve guides were worn, the seats were not hardened, and I did a lot of highway driving without lead. It now had hardened seats.
[/QUOTE] probably so.  but the lack of lead isnt why.
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Points: 4742 		Post Options Post Options   Thanks (0) Thanks(0)   Quote FSJunkie Quote  Post ReplyReply Direct Link To This Post Posted: Dec/04/2016 at 4:06pm
Where are you getting that information from? I am looking at two parts books right now. They show the following part numbers for six cylinder head assemblies:

1962-1973 Jeep J-series parts book:

Year
'71.........................812 0136
'72.........................812 0136
'73/.........................812 2375

1976 AMC parts book:

'74.........................812 2375
'74.........................812 3358
'75/.........................812 5454

I also quote the 1974 Jeep service manual page A-1:

"Eight cylinder engine upgrading includes new induction hardening of the exhaust valve seats (was six cylinder only) for greater service life. All engines can now operate on any type of normal fuel...regular grade, low-lead, or no-lead."

From that and the part numbers, it looks like midyear 1974 was when they switched to induction hardened seats.
--------------

Unleaded fuel without hardened seats caused my seats to fail.

Nothing that you or anybody else says is going to change my mind, because this is my engine that I built myself, and I know more about it than you or anybody else ever will. I saw my valves, seats, and guides before and after. You didn't. Respect my word.


Edited by FSJunkie - Dec/04/2016 at 4:19pm
1955 Packard
1966 Marlin
1972 Wagoneer
1973 Ambassador
1977 Hornet
1982 Concord D/L
1984 Eagle Limited
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Points: 16614 		Post Options Post Options   Thanks (0) Thanks(0)   Quote purple72Gremlin Quote  Post ReplyReply Direct Link To This Post Posted: Dec/04/2016 at 10:18pm
Originally posted by FSJunkie FSJunkie wrote:

Where are you getting that information from? I am looking at two parts books right now. They show the following part numbers for six cylinder head assemblies:




--------------

Unleaded fuel without hardened seats caused my seats to fail.

Nothing that you or anybody else says is going to change my mind, because this is my engine that I built myself, and I know more about it than you or anybody else ever will. I saw my valves, seats, and guides before and after. You didn't. Respect my word.
The AMC parts books mean nothing to me. simply because the parts are not availible.   Your 77 Hornet has been running unleaded gas since it was new.  they failed because you ground the hardened part of the seat out.  I was working on cars in 1977.  Ive seen some seats get worn out with leaded gas.  back in the day valve jobs was very common.  Ive done valve jobs myself.  and 99% of the time when the seats are worn out, the guides and valve stems are as well.  which is why I dont waste my time doing just a valve job.  the newer cars almost never have a valve job done, by the time most of them need one, the engine is shot.  been there too.  No I havent seen your 232, and I dont know it like you do.  but Ive seen too many engines run for years on unleaded when they were originally on leaded.  GM approved of unleaded gas in their engines in 1971. My 1972 owners manual and TSM says recommended to run low lead or unleaded. 
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Take a few ounces of gas and pour it down the carb then start it. If it does not start and run fine for at least a few seconds then you may be looking at a skipped timing chain or failed timing sprocket or timing gear. The gas down the carb will overcome any lean condition long enough for testing.
The nylon timing sprocket in my Javelin let go at 60000m.

I think the crack in the intake is a whole seperate issue. I have fixed manifolds before by taking a dremel with a cutting wheel and opening up the crack a bit and about 1/4" deep or more and drill some holes at the end(s) of the crack to stop travel then used jb weld high heat putty applied into the clean crack and holes with a butter knife and heatgun. 24 hors later put the manifold in an oven at 375f for 2 hours then cleaned up the patch with a dremel. It will be stronger if you do not dremel it after curing and jest leave it alone.

Edited by maximus7001 - Dec/05/2016 at 7:13am
1968 Javelin SST

1997 GMC Safari AWD

2001 Daewoo Nubira SX (Winnipeg only model)

1997 Honda Accord EX (Canadian Model)

Winnipeg, home of the Jets.
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Points: 16614 		Post Options Post Options   Thanks (0) Thanks(0)   Quote purple72Gremlin Quote  Post ReplyReply Direct Link To This Post Posted: Dec/05/2016 at 7:04pm
A huge vacuum leak will keep it from starting............... like above it could be 2-3 different issues  
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