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Engine Help diagnose random overheating??

  • Thread starter Thread starter TomOsiris
  • Start date Start date Apr 10, 2022
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chrlsful

Active Member
Mar 6, 2021
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Lawrence Swamp, S.Amherst, MA
May 2, 2022
#101
  • May 2, 2022
  • #101
used to use thread treatment (had copper in it) just got cached up & added to the problem. Changed to a newer type (CRC or some other name brand, 'permatex'?) not much better but some. Just started using the new (1, 2 yrs?) caliper grease. None back for nxt change but I think it'll B da best...
Again...alu to steel aint good~
 

7991LXnSHO

wanna catch the space herp
10 Year Member
Sep 1, 2010
7,387
2,745
194
Kearney, NE
May 2, 2022
#102
  • May 2, 2022
  • #102
chrlsful said:
used to use thread treatment (had copper in it) just got cached up & added to the problem. Changed to a newer type (CRC or some other name brand, 'permatex'?) not much better but some. Just started using the new (1, 2 yrs?) caliper grease. None back for nxt change but I think it'll B da best...
Again...alu to steel aint good~
Click to expand...
What I have been using is like a big, silver crayon. It’s not as messy as the more liquid stuff with a brush in the lid. It’s also slower to get all the threads coated to my satisfaction.
Is anyone else using caliper grease or is really sold on a certain brand and type of anti seize?
 

limp

wrap a little cheese around it and its a done
5 Year Member
Oct 4, 2020
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Florida
May 3, 2022
#103
  • May 3, 2022
  • #103
Is this similar to the modular ford engine spark plug problems I read about?
 

General karthief

wonder how much it would cost to ship you a pair
Mod Dude
Aug 25, 2016
27,829
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203
polk county florida
May 3, 2022
#104
  • May 3, 2022
  • #104
limp said:
Is this similar to the modular ford engine spark plug problems I read about?
Click to expand...
from hang'n around that shop for several years I noticed it was two spark plug problems, I think it was the 5.4 mod engine, blowing spark plugs out, and crud build up around the end of the plug that made them nearly impossible to remove.
I only remember twice when the head had to be removed
 
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TomOsiris

Member
May 19, 2019
68
16
18
CT
May 3, 2022
#105
  • May 3, 2022
  • #105
General karthief said:
from hang'n around that shop for several years I noticed it was two spark plug problems, I think it was the 5.4 mod engine, blowing spark plugs out, and crud build up around the end of the plug that made them nearly impossible to remove.
I only remember twice when the head had to be removed
Click to expand...
Funny enough, I had a 5.4 2v that also blew a head gasket.
The earlier 2v engines did not have enough threads in the head where the spark plug threads in, over time with enough vibration they would wiggle loose and start to vibrate, this vibration would eventually weaken the threads to a point where BANG we have liftoff and send a plug up through the hood.
When fomoco changed to a 3 valve 5.4 a few years later, they overcompensated and the plugs would actually get stuck in the head and be nearly impossible to remove without damaging the threads, similar to the situation I am in now.
 
Reactions: limp

General karthief

wonder how much it would cost to ship you a pair
Mod Dude
Aug 25, 2016
27,829
10,509
203
polk county florida
May 3, 2022
#106
  • May 3, 2022
  • #106
Steel used against aluminium with liquid flowing through it has a corrosive effect (electrolysis), you know, all that scientific crap I did pay any attention to in school.
I just have trouble remembering now.
 
Last edited: May 3, 2022

manicmechanic007

5 Year Member
Sep 26, 2017
2,524
709
143
Roy, Utah
May 4, 2022
#107
  • May 4, 2022
  • #107
You have the ones where the plug breaks in two and you have to go in with the Lisle 65600 tool to remove the bottom portion limp?
Do Tune it up more often 75k miles max
Do Clean the injectors (thru the rail using the special chit) and clean the plate / upper intake first with carb foam and then the plugs come out easier
Last one I did like that only one broke off
 

manicmechanic007

5 Year Member
Sep 26, 2017
2,524
709
143
Roy, Utah
May 4, 2022
#108
  • May 4, 2022
  • #108
 

manicmechanic007

5 Year Member
Sep 26, 2017
2,524
709
143
Roy, Utah
May 4, 2022
#109
  • May 4, 2022
  • #109
I still use the silver Permatex anti seize compound on spark plug threads
 
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limp

wrap a little cheese around it and its a done
5 Year Member
Oct 4, 2020
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Florida
May 5, 2022
#110
  • May 5, 2022
  • #110
manicmechanic007 said:
You have the ones where the plug breaks in two and you have to go in with the Lisle 65600 tool to remove the bottom portion limp?
Do Tune it up more often 75k miles max
Do Clean the injectors (thru the rail using the special chit) and clean the plate / upper intake first with carb foam and then the plugs come out easier
Last one I did like that only one broke off
Click to expand...
No, I have a real truck
 
Reactions: Boostedpimp and General karthief

7991LXnSHO

wanna catch the space herp
10 Year Member
Sep 1, 2010
7,387
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Kearney, NE
May 5, 2022
#111
  • May 5, 2022
  • #111
limp said:
No, I have a real truck
Click to expand...
I’d give you flack for having a Chevy truck, but with the Ford HD trucks having crunchy axle tubes and driveshafts lately, I won’t bother.
 

limp

wrap a little cheese around it and its a done
5 Year Member
Oct 4, 2020
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Florida
May 6, 2022
#112
  • May 6, 2022
  • #112
7991LXnSHO said:
I’d give you flack for having a Chevy truck, but with the Ford HD trucks having crunchy axle tubes and driveshafts lately, I won’t bother.
Click to expand...
I do not fit in fords... Not sure why, but they just are not built for my chubby little frame... Arm rests are the wrong height, seats don't every feel comfortable, pedals and steering wheel are out of whack ( for me)..... Chevy trucks are like the few times I have driven a 911.. OH MY, does this feel good...LOL
The verdict is out on my new truck... I rolled the dice and got the 3 liter straight six diesel chevy came out with in 2019. ( My truck is a 2020) While I love my truck, I REALLY love this engine, and I am the LAST person to ever think I would have a diesel.. My concern is this engine is an Engineers nightmare and if it turns up problematic, it will be ugly.....
 

manicmechanic007

5 Year Member
Sep 26, 2017
2,524
709
143
Roy, Utah
May 6, 2022
#113
  • May 6, 2022
  • #113
Your Chev Limp, can't be much worse than a new Ford even with some trouble down the road
Hell, Fords got trouble now
Our old still applies joke at ford for the GM boys was
"they just lease the new GM products because they cant afford to sell you one" (with all the recalls and problems)
Ford has so many problems now with sticking turbo vanes and ecoboost turbo lines failure et al. I do not blame anyone evermore for buying whatever
Hate to say it but IMO Tesla makes a good product these days
 

limp

wrap a little cheese around it and its a done
5 Year Member
Oct 4, 2020
5,457
2,889
173
Florida
May 6, 2022
#114
  • May 6, 2022
  • #114
manicmechanic007 said:
"they just lease the new BMW and Mercedes products because they cant afford to sell you one" (with all the recalls and problems)
Click to expand...
Fixed it for you.... I found out why German cars that sell for over 100K are for sale for 10K not too many years later...... TOO expensive to fix, and they need LOTS of fixin as they age.....
 
C

chrlsful

Active Member
Mar 6, 2021
278
37
38
Lawrence Swamp, S.Amherst, MA
May 25, 2022
#115
  • May 25, 2022
  • #115
"...using caliper grease..."
as is in evidence 'I aint a gud writer'.
"...Just started using the new (1, 2 yrs?) caliper grease. None back for nxt change but I think it'll B da best..."

But "Yes" I am happy spreadin CRC black caliper grease (silly cone I think?) all
around (as never-seize).
 

Mindseye007

5 Year Member
Oct 21, 2020
549
127
63
ontario
Aug 15, 2022
#116
  • Aug 15, 2022
  • #116
CAMTWO1070 said:
I find that using the wrong antifreeze is bad....Using anything other than green isnt good,,

On a 351w I bought for a core on my 408 project the guy removed the engine and cleaned it up pretty good then reassembled it and put it back in he used Orange Antifreeze and only put a few thousand miles on the truck before letting it sit for 4 months due to issues with thetransmssion...When I took the engine apart to do my 408 I took the heads off and a couple of the lil steamholes were clogged with a thick orange gel..

Theres a huge difference between orange and green antifreeze...The orange stuff is acidic and doesnt mix with green well or like being in engines that have green antifreeze residue inside the block and radiator and starts a chemical reaction....

The seal between the timing cover and block develops places for air to enter and water to escape.I find proper torque,indianhead shellac and a retorque after a few heat cycles helps but I also have a fix for that ..

When you get antifreeze in the oil it gets filtered out and eventually clogs the oil filter fast and can be detrimental to your engine..

I took 3/4" copper couplers and epoxied them into the waterpump cover then when I installed the cover I used MotoSeal to seal the tubes where they go into the engine block



The 4 long screws that attaches the waterpump to the engine needs thread sealer as this is another way for air to enter and antifreeze/water to escape..

Another thing I find is that intake manifolds need to be retorqued plus I put a lil Indian Head Shellac around the water ports on the intake gasket to prevent any possible leaks..

Another thing I find is if youre running MLS gaskets is the way you initially treat the engine..I do my initial startups on plain water and even though it says its not needed I do a retorque anyway as my 351w didnt come with aluminum heads from the factory.

Then theres the matter of buying the right headgaskets too...Some manufacturers list if the gasket is for a steel to steel,,aluminum to aluminum or an aluminum to steel application too..........

Usually renting a cooling system pressure tester helps find the leaks fast if there are any..I pump it up to the max pressure my radiator can produce and let it sit overnight with a sheet of cardboard underneath..

If you run the car with plain water or antifreeze thats less than the 50/50 mix and you didnt remove it all during the winter ice could of started a crack in a waterjacket too depending on how cold your winters get.............

I hope you get to the bottom of the problem..
Click to expand...
What happens when the water jacket gets a crack?
 

96pushrod

I think they're a little easier to get off
5 Year Member
May 15, 2018
1,530
871
133
Savannah
Aug 15, 2022
#117
  • Aug 15, 2022
  • #117
Mindseye007 said:
What happens when the water jacket gets a crack?
Click to expand...
It sends coolant into a cylinder, and also pressurizes the cooling system.
 

7991LXnSHO

wanna catch the space herp
10 Year Member
Sep 1, 2010
7,387
2,745
194
Kearney, NE
Aug 15, 2022
#118
  • Aug 15, 2022
  • #118
96pushrod said:
It sends coolant into a cylinder, and also pressurizes the cooling system.
Click to expand...
Maybe not at first, but either the crack will head to a bolt that will not stay torqued so the head gasket leaks, or it cracks to the cylinder area. another possibility is a leak to an oil pressure or oil return area. Those fluids do not do well when mixed. A cast iron block is strong, but remember it is also brittle and cracks are are hard to repair well in cast iron.
Flathead blocks that cracked in common places often could be run at least until the next rebuild using a boiler repair product plumbers also used for not water and steam heat systems. if a block is already apart, it's not worth putting new parts and mechanic in a can into a broken 5.0 block at this time.
 
Last edited: Aug 15, 2022

96pushrod

I think they're a little easier to get off
5 Year Member
May 15, 2018
1,530
871
133
Savannah
Aug 15, 2022
#119
  • Aug 15, 2022
  • #119
7991LXnSHO said:
Maybe not at first, but either the crack will head to a bolt that will not stay torqued so the head gasket leaks, or it cracks to the cylinder area. another possibility is a leak to an oil pressure or oil return area. Those fluids do not do well when mixed. A cast iron block is strong, but remember it is also brittle and cracks are are hard to repair well in cast iron.
Flathead blocks that cracked in common places often could be run at least until the next rebuild using a boiler repair product plumbers also used for not water and steam heat systems. if a block is already apart, it's not worth putting new parts and mechanic in a can into a broken 5.0 block at this time.
Click to expand...
No matter where it starts or ends, a cracked water jacket pretty much spells the end of most stock block sbfs.
 
Reactions: Mindseye007

Mindseye007

5 Year Member
Oct 21, 2020
549
127
63
ontario
Jul 2, 2023
#120
  • Jul 2, 2023
  • #120
96pushrod said:
No matter where it starts or ends, a cracked water jacket pretty much spells the end of most stock block sbfs.
Click to expand...
What would cause the water jacket to Crack? Putting it in neutral and reving it to redline? Or missing a gear while shifting hard and quick?
 
Last edited: Jul 2, 2023
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