RTH coolant flush- bad HG?
- Thread starter VonCannon
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Sounds like it but without seeing in person just a guess.
Certainly sounds like it..... does it overheat??
- Thread starter
- #4
No sir. Temp gauge doesn't move above halfway. I got a check engine light now. I will go to autozone and get a OBDII tomorrow. Hopefully it will give me a code. It starts out fine, but as it gets up to temp it starts stumbling.
Take one spark plug wire at the time while running. Becareful if you get zzzap. If the engine start stumbling that one is working keep going untill you find the one that dont change the engine stumbling. Once you find the cilinder take the spark plug off and see if it is wet or vapor is coming out the hole. I wouldn't run it at all until you find what it is. I hope this helps
While you are there rent a HG tester and see what it says.
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Make sure you don't have an air bubble in the system. If there is any air in there, it will overheat. Try running with the cap off a few cycles of the thermostat opening and closing.
Radiator pressure tester is your next step then maybe a leak down test.
Make sure you don't have an air bubble in the system. If there is any air in there, it will overheat. Try running with the cap off a few cycles of the thermostat opening and closing.
Radiator pressure tester is your next step then maybe a leak down test.
Make sure you also get the passenger front higher than the rest of the truck also. Helps burp the system.
Good point, and now that I think about it, both heaters need to be on. Also many trucks have a T fitting for flusing. It can be used to bleed air out.
You may have to mess with it for a while to get it all bled out.
Jump up and down on the bumper when the thermo stat is open.
A overheated motor can run badly, how hot did you get it? That makes me think more about a head gasket issue. Pull the plugs, keep them in order and check them out. You should see one or two that cleaner.
When you flushed the radiator did you get antifreeze on the plug wires? In my experience it messes up ignition wires. Especially if they are old and have dry rot cracks in them.
It's a good idea to do some diagnostics before you start tearing it apart. If you take the motor apart and don't find a problem, you won't be able to run diagnostics with it taken apart.
Radiator pressure test and then a leak down test if that is not conclusive.
It may be possible that you have an air bubble and plug wires damaged by coolant or you might just have a blown head gasket.
- Thread starter
- #14
10-4. I didn't get any fluids on plugs. I also have read up on burping the system and I believe i have done this. When I first start it it runs fine then as it warms up it gets worse. Almost like it is a vacuum issue. It sounds like all 6 are hitting at first.
What kinda cruiser you got?
Get a vacuum gauge, download a vacuum gauge how to guide:
http://www.classictruckshop.com/clubs/earlyburbs/projects/vac/uum.htm
If it was an F or a 2F I'd have a problem like that caused by a crack in the bottom in the intake manifold. As the motor warms up, the crack gets worse and it starts to leak vacuum really badly and it's vacuum fed by hot exhaust not just cold air - does a great job of making the thing run like crap. This can also happen when you need to rebuild your intake/exhaust manifold but in that case it's just a vacuum leak. I like to find them with oxygen from the torch or carb cleaner. First things, first - look for loose fasteners on the intake exhaust manifold. There are two hidden on the bottom. A Matco 17mm 1/2 drive flex impact socket makes tightening the one closest to the firewall much easier.
Remember, problems like this can often be caused by more than one problem. One exacerbates the other. A few small vacuum leaks mixed with one moderate one can have a significant effect.
Still could be a head gasket if tied to overheating though...
re-reading your first post again and thinking about it, I think you have a blown head gasket. You can get the milky oil from a clogged PVC system but this sounds like blown head gasket to me.
When you say white smoke do you mean just a little or do you mean smoke bomb or smoke screen? A little white smoke can be just the motor being cold, bad air fuel ratio or
Get a Radiator pressure tester thread it on and start it up cold. Follow the directions. Pull the plugs first and check them out. Also, does the white smoke smell kinda like cotton candy? When the glycol in the coolant goes through the combustion process it smells kinda like burning sugar. You can probably borrow the tool from auto zone. If you have a newer cruiser you may needed the smaller adapter.
You will see the coolant pressure spike
Smart to start with the codes on a newer motor. Maybe the coolant in the exhaust has taken out an o2 sensor or clogged a cat.
When you say white smoke do you mean just a little or do you mean smoke bomb or smoke screen? A little white smoke can be just the motor being cold, bad air fuel ratio or
Get a Radiator pressure tester thread it on and start it up cold. Follow the directions. Pull the plugs first and check them out. Also, does the white smoke smell kinda like cotton candy? When the glycol in the coolant goes through the combustion process it smells kinda like burning sugar. You can probably borrow the tool from auto zone. If you have a newer cruiser you may needed the smaller adapter.
You will see the coolant pressure spike
Smart to start with the codes on a newer motor. Maybe the coolant in the exhaust has taken out an o2 sensor or clogged a cat.
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Sorry if I missed the post, but grab a block tester from napa.
Get your rig at operating temp. (thermostat open) and use the block tester according to the directions on the bottle.
Green or yellow fluid= exhaust gas in antifreeze. =BAD.
Get your rig at operating temp. (thermostat open) and use the block tester according to the directions on the bottle.
Green or yellow fluid= exhaust gas in antifreeze. =BAD.
Where are you located??? I love coolant diag. for some reason. Haha