What is the likely effect of doing this over time? (Gas in radiator, misfire on one cylinder (P0301); gotta be the HG right?) Actually runs okay, or seems to. @NLXTACY and @Kay9Cop have had good luck with sealants, but they were also planning near-term rebuilds and I'm not sure that's in the budget. I run maybe 6k miles a year. Thanks for any help!
Running Engine with Blown Head Gasket... (1 Viewer)
- Thread starter jaymar
- Start date
This site may earn a commission from merchant affiliate
links, including eBay, Amazon, Skimlinks, and others.
If you're getting gas in the cooling system then i think your running days are numbered. If the cooling system pressureises above a certain point it will likely blow your radiator. If the HG leak is between cylinders then you might be ok but way down on power. Either way i struggle to see a reason to drive it any further than it takes to get it in the shop.
How about doing a compression check on all the cylinders? What do the plugs look like? I have coolant in the oil on my 80 but I’d expect that considering it’s almost got half a million miles on the original head gasket.
A misfire in the motor isn’t good for it.
A misfire in the motor isn’t good for it.
a misfire on one cylinder can be caused by any number of things. Might be a good idea to do some diag work.
- Thread starter
- #5
No danger on the radiator, which sprang a leak some time ago, before this problem arose (or so it seems, anyway). I check the water level before going anywhere; sometimes it's fine, other times it needs a half gallon or three-quarters. Sometimes it pukes water when parked after running, sometimes not. Have a new radiator but not putting it in while this is going on. Misfire felt rough at first, then seemed to smooth out. This is DD, though not driven daily. Available funds committed elsewhere for the moment...
- Thread starter
- #6
Don't have the gear but I can get it. When the misfire first showed up, I changed the plug; looked fine at that point. I'm running distilled water because the radiator leaks; if it looks like freezing temps (which is rare), I'll warm it up before bed. Coming up on 240k on original HG. You have coolant in your oil and it runs fine?
- Thread starter
- #7
True--but how many things can put fuel in the radiator? So far as I know, only the HG. But (obviously) there's a lot I don't know...
Are you watching the temps with a scan gauge? The misfire isn't great obviously but excessive water in the oil and/or overheating could really do a lot of damage.
If it's leaking it could cause pitting on the head or even the block which would require machine work
I'd try to drive any other vehicle that's available to you in the meantime.
Also can you take off the head yourself? That'd save you a lot of coin. Most independent LC shops charge around 3500 for a top end rebuild, though that ,may be the nest choice if you're not a fairly seasoned mechanic.
If it's leaking it could cause pitting on the head or even the block which would require machine work
I'd try to drive any other vehicle that's available to you in the meantime.
Also can you take off the head yourself? That'd save you a lot of coin. Most independent LC shops charge around 3500 for a top end rebuild, though that ,may be the nest choice if you're not a fairly seasoned mechanic.
Adding stop leak typically settles in oil cooler and clogs it. If you are leaking coolant into the engine, being it’s heavier than water, at some point the oil pump will suck it up and destroy the crank.
I’d stop driving it.
I’d stop driving it.
- Thread starter
- #10
Watch it like a hawk; typically high 180s to mid 190s, occasionally upper 190s to just over 200. Don't have another vehicle. Given enough time, I'm sure I could get the head off--but I'd have no vehicle for the duration. $3500 for the head rebuild alone--no pull/reinstall? That's getting to ballpark for a new, complete head, isn't it?
I get how fuel or a little oil can wind up in the coolant as piston compresses and fluid is forced out through blown gasket. But isn't it fairly unlikely that the downstroke will suck coolant (in this case water) when the valves are open and supplying fuel/air mix? Path of least resistance and all that...
Last edited:
- Thread starter
- #11
I think we can agree that it would be best not to run the engine, but not much choice at the moment. I don't know that there is coolant (distilled water at this point) in the engine; all I know is that there's fuel in the radiator. Two questions:
1) How low is the oil pickup--that is, how much room is there for bottom-dwelling water before it gets sucked up?
2) Assuming there is water in the oil, I can presumably buy time by opening the drain plug occasionally and changing the oil--or trying to drain water only from the oil pan plug, yes?
3) Bonus question: if #2 above can address the potential coolant/water issue--what else is there to worry about here?
AFAIK it's about the same cost as all the parts for a new cylinder head, but 3500 is parts and labor, at least that's what OTRAMM and Ozark Overkand Outfitters charge, but they're not on the west coast so it might be more out there.
I'm not sure on the second part tbh, but i think with Toyota's the "chocolate milkshake" isn'y always present: oil can look perfect when the HG is totally blown.
Check your dipstick. If you get water in the oil, it will destroy the entire engine in relatively short order. I bought an LX cheap that needs a new motor due to a small leak in the oil cooler.
- Thread starter
- #14
Thanks for the tip. Pull fast and look for water on the end? Does the dipstick go lower than the pickup?
If you are running it, the oil will mix with the water and you'll have a chocolate milkshake. It will be obvious. Shutting it down until you know what the problem is is your best bet, but do not run it with water in the oil. That means you may want to check it every time you run it.
Running it at all is a gamble.
It might be OK, until it isn't, then the results can be catastrophic.
If gasket fails and dumps coolant in a cylinder you risk hydro-locking the engine and bent rods, cracked head, cracked crank.
If water settles in the oil, you risk starting the engine with water at the main bearings and shredding bearings and damaging the crank beyond repair.
I had a head gasket fail in my 80, results included all of the above.
Expensive to repair, and demoralising!
It might be OK, until it isn't, then the results can be catastrophic.
If gasket fails and dumps coolant in a cylinder you risk hydro-locking the engine and bent rods, cracked head, cracked crank.
If water settles in the oil, you risk starting the engine with water at the main bearings and shredding bearings and damaging the crank beyond repair.
I had a head gasket fail in my 80, results included all of the above.
Expensive to repair, and demoralising!
Use a head gasket "fix" product containing sodium silicate and continue to run it while saving up for a V8 swap...
It's your money.
Pay now or pay more later.
Pay now or pay more later.
At least once a week around here I see someone driving along with water puking out their tailpipe. I always want to follow them and ask them questions like How often do you have to add water? How long have you been driving it like that? No idea what the answers would be, but I still bet some of them have been doing it for months at a minimum.
Coolant itself makes a decent engine lubricant. It's the emulsification of the engine oil with coolant that doesn't flow well and causes all the problems. Coolant by itself is great at heat transfer and it does actually lubricate a little.
I was involved with some crazy testing on this. Freightliner used to test it's semis to see how far a truck would drive with something wrong with it. When they first adopted the 60 series Detroit they had to redo a bunch of the old tests. For one of the tests they hooked a brand new truck to a trailer with your average 40K lb load on it. They drove 50 miles away from the main plant here in Portland. They drained all the engine oil and filled the sump with the same coolant that was in the radiator. Then they fired it up and hit the road headed back towards the plant. The goal was to see how far the truck would go in normal driving before major engine damage occurred. Well, the truck was bearing down on the exit to get off the freeway for the Freightliner plant and still doing fine so they told the driver to keep going. He went past portland 60 miles before they told him to turn around and come back. He made it back to the plant just fine and turned the engine off, no damage to the engine bearings. Just some turbo bearing wear and a couple gallons of coolant in the intercooler from the turbo puking it out.
