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lets talk blown head gaskets

5K views 54 replies 15 participants last post by  Delemorte 
#1 · (Edited)
head gaskets(Update pg2)

I dont know if i blew one or not but im gonna be poking around there and want to know symptoms of what im looking for...


if i blew a head gasket and got oil in my water would i be guarenteed to see water in my oil? Im not smoking or anything but im tracking down a water leak and oil in the water would explain the oil i saw in my bildge. A leaky valve cover gasket or pan gasket would also explain but i want to cover all my bases while im there.

Gonna be pulling the pan this weekend. Replacing headgaskets is no biggy but did not want to do it if it was not required. When i pull that pan, if i dont see any signs of water should that eliviate any concerns I might have for my head gasket? any other things to check with out pulling the heads off?
 
#7 ·
Depends on where the head gasket blew. Yes, a blown head gasket can cause water in the oil, but not always. Typically if they blow between the cylinder and the lifter galley you will definitely have water in the oil.

A common place for water to get in the oil is the intake manifold gaskets where the water crossover in the intake manifold is.
 
#8 ·
Depends on where the head gasket blew. Yes, a blown head gasket can cause water in the oil, but not always. Typically if they blow between the cylinder and the lifter galley you will definitely have water in the oil.

A common place for water to get in the oil is the intake manifold gaskets where the water crossover in the intake manifold is.
sbc don't usually blow there;) lotta bolts on a sbc intake, i say its a headgasket:)bulb
 
#10 ·
and lets not foget. I have not found water in the oil. The actual question is "If i DONT find water in my oil, should i even look further at a possible head gasket failure?"

oil is leaking some where and it could just be a shitty valve gasket or pan gasket or could be something internal. Hoping not to pull the heads if not required. I dont mind doing it but dropping the jack on another head gasket and bolts pisses me off if it aint required. :) then again i could allways pull the engine and if i am still loosing oil after putting it back i can replace the head gaskets then with out removing the engine from the boat.:)eh:)


now if i do find water in there ill pull the heads regardless...
 
#12 ·
OK, to answer your question, no water in the oil does not mean that the head gasket can't be blown. They can blow between cylinders, or between the cylinder and the outside of the cylinder head, etc etc.
 
#24 ·
Thats alot of work to find out you dont have an internal problem. Start with the easy stuff first. There is probably a board member that lives near you that could help you out with a leak down test if you dont have the tools. Have you done an oil change to see if you have water or checked the valve covers for tell tale signs?
 
#20 ·
I saw this happen this year. The guy that bought my old boat ran it with a popped freeze plug and loaded the boat with water! (above crank) Then he called me asking about a block! Milkshake big time thought busted block! Turned out that water had worked it's way back into block through crank seals! Changed oil a couple times and and no milkshake! Just info. WT:)devil
 
#22 ·
if i blew a head gasket and got oil in my water would i be guarenteed to see water in my oil? Im not smoking or anything but im tracking down a water leak and oil in the water would explain the oil i saw in my bildge. A leaky valve cover gasket or pan gasket would also explain but i want to cover all my bases while im there.
Does this thing have an oil cooler?



 
#34 · (Edited)
Update..

Ok.. So i pulled the spark plugs valve covers and did a compression test. I think i found the source of my oil but still concerend about compression test. Please let me know what you think all the way around.


Compression test: Dry and about 90 degrees.
Cyl 1: 125 PSI
Cyl 3: 100 PSI
Cyl 5: 130 PSI
Cyl 7: 130 PSI


Cyl 2: 155 PSI
Cyl 4: 150 PSI
Cyl 6: 145 PSI
Cyl 8: 145 PSI

Not sure how these plugs look but they are uniform. Unlike prior to my head gasket change where 5 and 6 were black. about 7 hours on plugs

Driver side


Passanger side


As you can see from my exhuast and the fact that the plug boots and plugs themselves are covered in burnt up oil. I believe the oil leak is from leaking valve cover gaskets. the picture illistrates whats up...





New Valve covers.. yea BLING!!!!:)devil


Didnt install gaskets correctly.. bad little monkey...:|err



Pulled valve covers. No signs of exsessive moisture.



Also the dip stick reads just a .5 quart low so i pulled it out of the water before the oil got to low or temp got to high. Never got above 150 degrees..
 
#37 ·
Yes the Duece and half, veitnam era vehicle, will run on any fuel. It has a multi fuel deisel engine. The engine life is shortened drasticly running on gasoline. And it is an alternate emergency fuel for that vehicle. The duece and half would pretty much run on swamp gas if you could fill the tank with it. The UH-1 would fly on JP4 or JP8 and had white gasoline (unleaded) listed as an emergency fuel. Never saw one run on it, but the -10 (operators manual) had it printed in it.
and any diesel can run off of gasoline if you had to, it would just run like shizz and go into a limp mode. my ford manuel says that if i had to, i could, but its not recommended. ive had some training in the above fuels, did 9 and a half years in the corps before they medically retired me
The "Deuce", 2 1/2 ton general purpose millitary truck, I was driving arround Baghdad Intl. Airport (formerly marked, even while I was there as 'Saddam International Airport' (in English and Arabic)) May, June, July 2003, was marked, very well, on the dash and on the fuel tank, to fuel with EITHER diesel fuel or 87 octane unleaded.
Really care to continue Impatient1???????????

I have a 3 or 4' section of 1" Sched. 40 PVC in the garage left over from replacing my house incoming water main line some years back............................
 
#39 ·
Turns out I was wrong on the PVC..................

Rating is 450 PSIG @ 73*F, not 150 PSIG :)
 
#44 ·
I do have a pressure bypass set up on the water line heading into the block. At WOT block water pressure is 15-18 PSI. However i do not have any valves set up between the T-stat housing and the t-valve. (Note T-stat housing does not have a t-stat in it).



And one side being that much different than the other was a concern. Thats what i needed an opinion on. Repalcing the head gaskets aint a thing. I can do that while i got this all apart. Think i should do it?
 
#45 ·
How did it run before you took it apart? If it ran ok I would run it till winter and do a complete rebuild, a blown head gasket isn't going to effect all four cyl,s and if blown between cylinders would cause it to run like crap and would be very noticable. Did you run the comp. test on the low side last, possible battery getting low and not spinning the engine as fast when testing that bank?
 
#46 ·
As a matter of fact its been running great.. Minus the oil leak and water leak which are both explained elsewhere. Also i tested the low side first and went back after the other side to just double check and it had the same readings.
 
#49 ·
Those plugs look good, the low compression readings on an entire bank is a real oddity.

Re-run all valve adjustments and re-test is my best idea right now.

See if the pressures change, or equalize more, try to be as exact as possible on the valve adjustment.

What valvetrain are you running BTW?
 
#55 ·
World already got back to me.. Wow they are fast.

They said the castings are the same. However those heads come in a 64cc and 72 cc. No way to tell what cc they are with out pulling the heads and measuring.. So, ill go thru the valves again to make sure they are correct then next time i pull the heads ill measure the chambers. However as long as shes running good i probably wont screw with it too much.
 
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