Joined
·
49 Posts
Hg is blown on the T. Don't want to pay $2,500 for a shop to replace them. I've never tore down a DOC engine before. Any tips, secrets or precautionary advice would be great appreciated!
Replacing head gaskets
1 - 20 of 23 Posts
Joined
·
5,712 Posts
Just be sure you have a shop manual which shows you how to align the cams when you reassemble it, I believe. It's a ton of work, but it is doable.
If you are considering ever getting headers, now would be the time, as well, since you'll be taking off the manifolds anyway.
If you are considering ever getting headers, now would be the time, as well, since you'll be taking off the manifolds anyway.
Joined
·
49 Posts
I already have JBA LTs with full Cajun exhaust.
I dread removing the headers again.
A friend of mine says on his Nissan car he dropped in drill bits to keep timing in place.
How much harder is the job leaving the engine in the truck and just removing everything on the front of the truck than pulling the engine?
I dread removing the headers again.
A friend of mine says on his Nissan car he dropped in drill bits to keep timing in place.
How much harder is the job leaving the engine in the truck and just removing everything on the front of the truck than pulling the engine?
Joined
·
49 Posts
I do dread the job.
Haven't performed a compression or leak down test but all signs and symptoms are point towards the head gasket
Rough idling/ multiple random misfires
Overheating
Excessive coolant consumption
White smoke
Oil in the coolant reservoir
Haven't performed a compression or leak down test but all signs and symptoms are point towards the head gasket
Rough idling/ multiple random misfires
Overheating
Excessive coolant consumption
White smoke
Oil in the coolant reservoir
Joined
·
661 Posts
You can do it with the engine in the truck, be sure to remove the hood and be careful with the harness plug clips. Like they said, have and FOLLOW the service manual. I would recommend removing the engine if you could, it would be easier in the long run due to the rtv.
Joined
·
49 Posts
I'm starting to second guess the head gasket issue before I tear into only because I really really don't want to open this can of worms.
I pulled the guts out of an old thermostat so I could still have a ring for the gasket to go around yet let the coolant be free flowing. I don't have any rough idling or misfires now. I haven't taken it for a long drive but the truck isn't overheating now as it use to spike and fall within 3min of driving. I use to not have any heat except for in high RPMs and now I have constant heat. I got home from work at 3:30pm went out tonight around 6:30pm to remove the resirvoir cap to check coolant levels and the system still had pressure on it after 3hrs.
The engine fires immediately like a champ with the loud growl the Titan is known for. I still have excessive white smoke while idling and have some brown "burnt" crud on my bumper above my exhaust tips. Oil is still very clean.
Anyone have any other input or are we still leaning towards a head gasket? I'm hoping for anything besides a head, a gasket, valve seals etc.
I pulled the guts out of an old thermostat so I could still have a ring for the gasket to go around yet let the coolant be free flowing. I don't have any rough idling or misfires now. I haven't taken it for a long drive but the truck isn't overheating now as it use to spike and fall within 3min of driving. I use to not have any heat except for in high RPMs and now I have constant heat. I got home from work at 3:30pm went out tonight around 6:30pm to remove the resirvoir cap to check coolant levels and the system still had pressure on it after 3hrs.
The engine fires immediately like a champ with the loud growl the Titan is known for. I still have excessive white smoke while idling and have some brown "burnt" crud on my bumper above my exhaust tips. Oil is still very clean.
Anyone have any other input or are we still leaning towards a head gasket? I'm hoping for anything besides a head, a gasket, valve seals etc.
Joined
·
5,712 Posts
As one of my sales managers frequently said, "Hope is not a strategy."
The only way to handle something like this is to do a compression test, and then a leak down test. But it definitely sounds like you had a sticking thermostat and perhaps have a flow issue with the water pump. Trouble is, you may have a head gasket blown between the cylinder and water jacket, and the only way to know is to check it. Might be worth paying the $100 to have a shop diagnose it, if you have one you trust.
The only way to handle something like this is to do a compression test, and then a leak down test. But it definitely sounds like you had a sticking thermostat and perhaps have a flow issue with the water pump. Trouble is, you may have a head gasket blown between the cylinder and water jacket, and the only way to know is to check it. Might be worth paying the $100 to have a shop diagnose it, if you have one you trust.
Joined
·
4,258 Posts
Get a cooling system pressure tester. Put the tester on it and apply pressure, if you see the pressure drop over a period of time, then there is a leak somewhere or you have a bad HG.
If no pressure drop, then do a compression test. If it checks out, do a leak down test. Then if that checks out, your most likely all good!
If no pressure drop, then do a compression test. If it checks out, do a leak down test. Then if that checks out, your most likely all good!
Joined
·
661 Posts
Dont forget a block test. So many condemn their HGs without doing this. A local shop can do this or you can get a kit for a decent price. Its always better to get a professional diagnosis before you spend $$$ on a shotgun diagnosis. Just know that there are hidden cost no matter what you do. IMO this is one of the more difficult engines to pull so if you dont have the means or expertise to complete the job, it may be worth while to pay the cost.
Joined
·
2,437 Posts
You may notice that the cooling system will pressurize almost immediately after a cold startup if you have a bad head gasket. Water in the oil, random misfiring, overheating, coolant loss, and steam with traces of smoke in it are all signs of a bad gasket.
Joined
·
49 Posts
Update... bit the bullet and took it to the shop. $3,318 for the job. It's been 3 weeks since I took it in and still haven't got it back yet
Joined
·
122 Posts
Hopefully it was a head gasket issue then!
The only real trick with a OHC engine compared to one with the cam in the block is dealing with the cam timing. There are lots of kits out there to lock to the crank and cams but that is not necessary...just don't rotate the cams or crank while the heads are off. Or if you do, the service manual covers the procedure to align them again.
It does help if you turn the engine to TDC / 0o before you start because then you can use the alignment marks to check everything is OK.
Also when you've assembled, always turn the crank twice to make sure nothing is interfering, if you have done it wrong and hit the starter button you can stuff a whole heap of expensive valves
The only real trick with a OHC engine compared to one with the cam in the block is dealing with the cam timing. There are lots of kits out there to lock to the crank and cams but that is not necessary...just don't rotate the cams or crank while the heads are off. Or if you do, the service manual covers the procedure to align them again.
It does help if you turn the engine to TDC / 0o before you start because then you can use the alignment marks to check everything is OK.
Also when you've assembled, always turn the crank twice to make sure nothing is interfering, if you have done it wrong and hit the starter button you can stuff a whole heap of expensive valves
Joined
·
49 Posts
It's the first time I've ever had to take a vehicle to a shop and I'm a little heartbroken because I couldn't tackle it myself lol.
The shop owner said he was replacing the timing gears and chains, any valves and lifters that are bad, resurfacing the heads and anything else which is wore out. It's a small shop but the guy is very honest and I know he isn't charging for random things just to make an extra dollar.
He just doesn't get in a hurry and takes forever
The shop owner said he was replacing the timing gears and chains, any valves and lifters that are bad, resurfacing the heads and anything else which is wore out. It's a small shop but the guy is very honest and I know he isn't charging for random things just to make an extra dollar.
He just doesn't get in a hurry and takes forever
I got into this too late to be much help. In the future, if you suspect a head gasket issue there are two more shadetree diags you can do that will help you decide your next step when you don't have the pro equipment and tools at hand. 1; if you see yellow/gray goo under the oil filler cap and under the radiator cap...that's a good indication of a head gasket problem. 2; with the radiator cap off, bring the engine up to temp and watch the radiator fluid while flipping the throttle....gas bubbles, lots of them will escape as rpm's increase and pretty much disappear as the throttle drops.
The only gotcha in that #2 test is the issue of a closed thermostat (which would also show up as the overheating) blocking the combustion gas leak. The closed thermo wouldn't mean you don't have a blown head gasket, in fact, it could have been the cause!
The only gotcha in that #2 test is the issue of a closed thermostat (which would also show up as the overheating) blocking the combustion gas leak. The closed thermo wouldn't mean you don't have a blown head gasket, in fact, it could have been the cause!
Joined
·
49 Posts
I gutted my thermostat for continuous flow and it still over heated. There was no coolant in my oil. I did the block leak test and the blue liquid turned to yellow so that was enough for me to suspect it was a head gasket. Truck has a new radiator, coolant hoses, water pump and a gutted thermostat.
1 - 20 of 23 Posts
