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General Information => General => Topic started by: Chuck on July 08, 2010, 12:00:42 pm

Title: Overheated engine Help with Mechanic in Northern CA
Post by: Chuck on July 08, 2010, 12:00:42 pm
 
 Ok started easy enough just ran a little hot no fan - replaced sensor  Still too hot - TReplaced T Stat still too hot - Took out expensive T stat would not open but original did  Put bact the original  Still too hot , Replaced Rad still too hot  Checked W Pump using bentlys  = Good 

Replaced Expansion cap Still....

SO  I have a bad head gasket  - no water in oil no water out the exhaust - But <ugg>  now the top Rad hose blows up like a balloon when engine is running and new cap is on.

Now  comes the help question  No way I can afford dealer cost to replace gasket ( and maybee head)  so anyone working on their own here in the Northern California area?

I dont mind paying the mechanic  But paying the dealers family more than the Mecanic is...... too costly.

81 Rabbit 114K miles 5 speed  good shape otherwise.

Thanks

Chuck

Title: Re: Overheated engine Help with Mechanic in Northern CA
Post by: burn_your_money on July 08, 2010, 12:05:33 pm
It sounds like you have a bad rad cap. Even with a bad headgasket the hoses shouldn't blow up like that.

What you need to do is have the engine dead cold. Remove the rad cap and then replace it. Start the car and run it for 10 seconds. Shut car off. Remove rad cap. If it's pressurized then yes you have a headgasket problem. You can also look for bubbles in the expansion tank when it is running. If they are present then it is the headgasket.

How did you check the waterpump?
Title: Re: Overheated engine Help with Mechanic in Northern CA
Post by: Chuck on July 08, 2010, 01:43:12 pm
It sounds like you have a bad rad cap. Even with a bad headgasket the hoses shouldn't blow up like that.

What you need to do is have the engine dead cold. Remove the rad cap and then replace it. Start the car and run it for 10 seconds. Shut car off. Remove rad cap. If it's pressurized then yes you have a headgasket problem. You can also look for bubbles in the expansion tank when it is running. If they are present then it is the headgasket.

How did you check the waterpump?

Thanks for the reply

 New Rad Cap  as of today   old cap appearently vented the pressure out as this one - not cold but only warm - will blow up the hose in ( make it bulge and hard) in seconds remove cap and  sounds like an air hose when you remove a tool  :'(  I have been going round and round with this for more than a week now  and untill today have not seen the Hose thing  - only after the New Blue cap.

OH WELL   I was thinking of a turbo anyway and would need bigger studs and the glow plugs should be changed and I need more luberacating fluid on my hands

SO maybe it's a loose win

Again Thanks

Chuck

Title: Re: Overheated engine Help with Mechanic in Northern CA
Post by: RadoTD on July 08, 2010, 08:04:18 pm
Does your lower rad hose get hot?
Mine didn't for the longest time, couldn't figure it out. Then I decided to remove the one plate from my thermostat (the one that goes further into/towards the block) and it works now. Just in time for some great weather here! :)

I still have the one plate that fully closes blocking off the thermostat housing so my cooling system functions/warms up completely normally
Title: Re: Overheated engine Help with Mechanic in Northern CA
Post by: Chuck on July 08, 2010, 09:33:36 pm
Does your lower rad hose get hot?
Mine didn't for the longest time, couldn't figure it out. Then I decided to remove the one plate from my thermostat (the one that goes further into/towards the block) and it works now. Just in time for some great weather here! :)

I still have the one plate that fully closes blocking off the thermostat housing so my cooling system functions/warms up completely normally

WEll I have had the Thermostat housing OFF several times Never saw A "Plate"  I can reach the impeller with my finger I used a screw driver to wedge the impeller to see if it turned while the pully was turned  NO  it was solid.  ( Bentlys Methoud)

 All the time I was dooing the parts investigation I never saw  the upper hose bulge .  untill I put the new Cap on.  and there is the air pressure  Maybe the engine was hotter than I thought?

And NO the lower hose did not get hot Nor the left side of Rad ( sensor side)

I havent given up Yet BUt  No water in Oil No white smoke  I could just have a huge blockage in the water passages in the head But  wont know till  I have to take it off.

Thanks

Chuck
Title: Re: Overheated engine Help with Mechanic in Northern CA
Post by: Luckypabst on July 08, 2010, 10:47:59 pm
Regardless of the cap or engine temp, the hose definitely should not pressurize "in seconds" after putting the cap on.

Check a full pressure tank with the cap off, engine running, for bubbles if you want to confirm the head gasket...

Chris
Title: Re: Overheated engine Help with Mechanic in Northern CA
Post by: mystery3 on July 08, 2010, 11:06:53 pm
Where in northern California? This half of the state is bigger than half of the states.
Title: Re: Overheated engine Help with Mechanic in Northern CA
Post by: Chuck on July 08, 2010, 11:14:07 pm
Regardless of the cap or engine temp, the hose definitely should not pressurize "in seconds" after putting the cap on.

Check a full pressure tank with the cap off, engine running, for bubbles if you want to confirm the head gasket...

Chris

 Chris
 
I have looked into the tank but it's hard to see bubbles as the small top hose is spitting water into the tank ( or is that what you meant ?)
Title: Re: Overheated engine Help with Mechanic in Northern CA
Post by: Chuck on July 08, 2010, 11:16:55 pm
Where in northern California? This half of the state is bigger than half of the states.

 I'm near Sacramento  But I can trailer  I dont expect this would be a one day thing ;D so a trip to deliver is not a killer to find the right person/shop.

Chuck
Title: Re: Overheated engine Help with Mechanic in Northern CA
Post by: Luckypabst on July 09, 2010, 09:21:07 am
Fill the tank to above the bleed hose level, almost to the top of the filler neck and watch it at various RPM. Air bubbles should be pretty obvious if there's a leak - it'll be distinctly different than the turbulence caused by the bleed line.

Chris
Title: Re: Overheated engine Help with Mechanic in Northern CA
Post by: Baron VonZeppelin on July 09, 2010, 10:02:19 am
"Possibly" you have fixed all the pre-exisiting ailments - and just need a new top hose now.

The air and heat "may" be from trapped air in system.

Before pulling the head, i would remove thermostat completely, turn heater selection to hot, remove all or most hoses and flush the ever living helk out of everything with a garden hose nozzle at every opening in every direction.

If you have a metal distribution pipe that runs from water pump up over and around to the heater core - remove it and inspect its innards while in the process.

Re-assemble, leave t-stat OUT, test run and check results.
With new top hose of course.
Would definitely give it a try before pulling head.
Title: Re: Overheated engine Help with Mechanic in Northern CA
Post by: RadoTD on July 10, 2010, 11:54:56 pm


Re-assemble, leave t-stat OUT, test run and check results.
With new top hose of course.
Would definitely give it a try before pulling head.

This ^^


And here's a pic of what my thermostat looks like... I cut the bottom plate off, that solved my overheating issue
(http://www.autohausaz.com/secure/PartImages/056121113A.jpg)
Title: Re: Overheated engine Help with Mechanic in Northern CA
Post by: 745 turbogreasel on July 11, 2010, 01:56:53 am
Also, pull both hoses from the engine, and confirm water CAN move freely though the rad side of things.
Title: Re: Overheated engine Help with Mechanic in Northern CA
Post by: Rabbit on Roids on July 11, 2010, 06:36:23 am


Re-assemble, leave t-stat OUT, test run and check results.
With new top hose of course.
Would definitely give it a try before pulling head.

This ^^


And here's a pic of what my thermostat looks like... I cut the bottom plate off, that solved my overheating issue
(http://www.autohausaz.com/secure/PartImages/056121113A.jpg)

if you cut it all apart, that seems like it would make it over heat worse, as most of the water flowing around never even sees the radiator..
Title: Re: Overheated engine Help with Mechanic in Northern CA
Post by: Chuck on July 11, 2010, 07:04:49 am
 
 Ysterday I filled everything up - Engine cold- Started and the ecpansion tank looked like it was boiling ( no heat just lots of bubbles or water movement)

I can feel air pressure BY hand when covering Tanke opening  Using cap tighten ( engine running) and top hose expands - losen one turn  - PSSSTT! Hose shrinks - repeatable .

Theres nothing IN the cooling system that can emulate an air compressor ( when cold) soo....  Cars now going to have to wait till I can find a head  Interesting that there is no water in oil or out the exhaust..

Thanks  for all the input.

Chuck  with the four cylinder air compressor.
Title: Re: Overheated engine Help with Mechanic in Northern CA
Post by: Rabbit on Roids on July 11, 2010, 07:06:42 am
sounds like the cracks between your valves might be just a BIT too DEEP...
Title: Re: Overheated engine Help with Mechanic in Northern CA
Post by: Baron VonZeppelin on July 11, 2010, 09:01:15 am
Theres nothing IN the cooling system that can emulate an air compressor ( when cold)

True.
Not easy to work with problems over webnet.
Sometimes some engines have probo on refill with air pockets, due to tstat location. Normally they work themselves out sooner or later. While present - they form steam and excess pressure etc...

Leaving out tstat would eliminate that condition on a troubleshoot.

RoR probably has your diagnosis.
A compression test would be real good info.
Harbor Freight has the Diesel Comp Tester on sale right now for $17-18. Usually $25. A lot of us have that exact tool - its a good tool.
Title: Re: Overheated engine Help with Mechanic in Northern CA
Post by: Rabbit on Roids on July 11, 2010, 11:10:37 am
HF diesel compression gauge <3
Title: Re: Overheated engine Help with Mechanic in Northern CA
Post by: 745 turbogreasel on July 11, 2010, 01:24:40 pm
sounds like the cracks between your valves might be just a BIT too DEEP...
IMO  a head gasket  leak to coolant passage is way more likely, by at least 20-1 odds in my experience.
Title: Re: Overheated engine Help with Mechanic in Northern CA
Post by: Vincent Waldon on July 11, 2010, 02:53:50 pm

  Interesting that there is no water in oil or out the exhaust..

Here's one way to look at it:

Water pressure (when cold) = 0 psi
Oil pressure = 50 psi or so
Compression pressure = 400 psi

Guess which system wins the battle of the pressures when there's a head gasket leak between the cylinder and the water jacket?  Between the oil gallery and the water jacket?

Hence, easy for the water jacket to get pressurized with no sign of water in the exhaust.  Same rational as to why you almost always see oil in the water but not the other way round.
Title: Re: Overheated engine Help with Mechanic in Northern CA
Post by: Rabbit on Roids on July 12, 2010, 09:49:53 am
sounds like the cracks between your valves might be just a BIT too DEEP...
IMO  a head gasket  leak to coolant passage is way more likely, by at least 20-1 odds in my experience.

if it got over heated, my bet is on the cracks opening up.. diesels DO NOT LIKE HEAT..
Title: Re: Overheated engine Help with Mechanic in Northern CA
Post by: 745 turbogreasel on July 12, 2010, 11:54:05 pm
They don't like it, but I've fixed probably more than 20 from overheating and headgasket failure...all warped and or leaking, but the only one which went into water was a bad injector which burned the burned a hole through the prechamber(http://forums.turbobricks.com/images/smilies/dunno.gif)

I'm of the opinion inter valve cracks grow over time regardless of operating temps.