Head gasket failure-3rd in 2½ years
Forum rules
By using this site, you agree to our rules. Please see: Terms of Use
By using this site, you agree to our rules. Please see: Terms of Use
- ndevans
- Minor Legend
- Posts: 1088
- Joined: Fri Mar 03, 2006 11:56 am
- Location: Bristol, England
- MMOC Member: Yes
Re: Head gasket failure-3rd in 2½ years
Been a while since I last posted in here. The refaced head is back in, with new gasket. I bought a straight edge, and the block appears, as far as I can tell, to be flat and square in all directions. So far I've done around 350 miles, and there is no sign of the weep of oil from the head next to no. 1 cyl, which is hopefully a good sign. I've also fitted a duplex timing chain, and it seems to run well generally.
However, on a long motorway run, I found the temp gauge hovering around the 195-205°F mark. This was at a steady 60, on a mild day, not a hot one. On occasion it would push peak at just short of 210°F, but would fall back to around 195-205°F after a few min. I have fitted a new 88°C (190°F) thermostat, and there was no discernible loss of water.
My radiator is over 30 years old, and, although it seems to pass water from a hosepipe freely enough, I suspected it was partly blocked, so I've swapped out for a new one. The temp gauge now hovers around 160°F (70°C), though I've only done short 5-7 mile runs so far.
So it could be that my head gasket problems were caused by overheating due to the radiator not flowing properly, but I am slightly concerned that the gauge is now not going over 160°F, as if that is correct, the thermostat wouldn't be opening.
However, on a long motorway run, I found the temp gauge hovering around the 195-205°F mark. This was at a steady 60, on a mild day, not a hot one. On occasion it would push peak at just short of 210°F, but would fall back to around 195-205°F after a few min. I have fitted a new 88°C (190°F) thermostat, and there was no discernible loss of water.
My radiator is over 30 years old, and, although it seems to pass water from a hosepipe freely enough, I suspected it was partly blocked, so I've swapped out for a new one. The temp gauge now hovers around 160°F (70°C), though I've only done short 5-7 mile runs so far.
So it could be that my head gasket problems were caused by overheating due to the radiator not flowing properly, but I am slightly concerned that the gauge is now not going over 160°F, as if that is correct, the thermostat wouldn't be opening.
-
- Minor Legend
- Posts: 1666
- Joined: Thu May 12, 2016 6:33 am
- MMOC Member: No
Re: Head gasket failure-3rd in 2½ years
Nowt wrong with 90 degrees Celsius - but does depend on the accuracy of your readout. Do check its accuracy before posting (most fail to do so).
The radiator is easily checked for blockage (sensible before replacing unnecessarily).
I suppose you have fitted the fan blades in the correct orientation?
Did running the heater circuit make any difference? A very obvious way to go, should a real overheating situation arise?
Is the fan belt loose?
Was the temperature variation at all due to gradient?
I’ll not go into oil pressure at these times - there is likely only an ‘idiot light’ fitted, so probably no indication to check.
How accurate is the speedometer reading? They are notoriously inaccurate.
What is the differential ratio? That can make a difference if over-loading the engine.
Is you timing (advance/retard) working correctly?
The radiator is easily checked for blockage (sensible before replacing unnecessarily).
I suppose you have fitted the fan blades in the correct orientation?
Did running the heater circuit make any difference? A very obvious way to go, should a real overheating situation arise?
Is the fan belt loose?
Was the temperature variation at all due to gradient?
I’ll not go into oil pressure at these times - there is likely only an ‘idiot light’ fitted, so probably no indication to check.
How accurate is the speedometer reading? They are notoriously inaccurate.
What is the differential ratio? That can make a difference if over-loading the engine.
Is you timing (advance/retard) working correctly?
- ndevans
- Minor Legend
- Posts: 1088
- Joined: Fri Mar 03, 2006 11:56 am
- Location: Bristol, England
- MMOC Member: Yes
Re: Head gasket failure-3rd in 2½ years
I checked the radiator by pushing a hosepipe into the top pipe & watching water come out of the bottom, then repeating the other way round, also by stopping up the bottom pipe, filling and watching it empty when the bottom pipe was unblocked. It seemed to flow well enough, but that's a blunt, unscientific yes and I have nothing else to go by.
Fan blades are the correct way round, belt was tight, oil pressure steady at 55-60, I didn't try the heater because the valve isn't accessible from inside the car currently, the cable isn't connected. I have tested the gauge or of the car, with the bulb in a pan of boiling water, along with a thermometer. It's not far out. Gradient did make a difference, but not massively. It did get hotter on climbs and cooler going downgrade, but it fluctuated also when on the level.
I'm more concerned now that it's running a little too cool.
Fan blades are the correct way round, belt was tight, oil pressure steady at 55-60, I didn't try the heater because the valve isn't accessible from inside the car currently, the cable isn't connected. I have tested the gauge or of the car, with the bulb in a pan of boiling water, along with a thermometer. It's not far out. Gradient did make a difference, but not massively. It did get hotter on climbs and cooler going downgrade, but it fluctuated also when on the level.
I'm more concerned now that it's running a little too cool.
-
- Minor Addict
- Posts: 721
- Joined: Sun Jun 21, 2015 9:41 am
- Location: Glasgow
- MMOC Member: Yes
Re: Head gasket failure-3rd in 2½ years
I presume one could use the later A+ flanged nuts on the original A studs, but only torque them to 45lbs? And thus eliminate the need for the separate washers?philthehill wrote: ↑Sun Jun 13, 2021 5:49 pm Only set the nuts to 50lbf ft if you have the correct studs which can be identified by a pointed top, a dimple in the top or a Y on the top.
High tensile flanged steel nuts should be used with the marked studs.
- ndevans
- Minor Legend
- Posts: 1088
- Joined: Fri Mar 03, 2006 11:56 am
- Location: Bristol, England
- MMOC Member: Yes
Re: Head gasket failure-3rd in 2½ years
I had a flanged nut on a standard A series stud for years, I always did it up to 45 with no worries.
-
- Minor Legend
- Posts: 3635
- Joined: Fri Apr 11, 2008 7:28 pm
- Location: Mansfield, Nottinghamshire.
- MMOC Member: Yes
Re: Head gasket failure-3rd in 2½ years
I've noticed my cars run hotter with the advent of this ethanol based fuel we have to use these days, so perhaps what we consider to be 'normal running temperature' needs to be revised?
Best wishes,
Mike.
Best wishes,
Mike.
1954 Series 2: 4 door: "Sally" -- Back on the ground with (slave) wheels and waiting to be resprayed......
1970 Triumph Herald 1200: "Hetty" -- Driven back from Llangollen in Wales (twice.....)
1970 Triumph Herald 1200: "Hetty" -- Driven back from Llangollen in Wales (twice.....)
-
- Minor Addict
- Posts: 769
- Joined: Sat Oct 31, 2009 8:51 pm
- Location: Epsom, Surrey
- MMOC Member: No
Re: Head gasket failure-3rd in 2½ years
Fan blades should only fit one way.
-
- Minor Legend
- Posts: 1053
- Joined: Tue Nov 08, 2016 3:18 pm
- Location: Manchester ( Damp and Miserable ) and that's just the wife...
- MMOC Member: Yes
Re: Head gasket failure-3rd in 2½ years
...and even if they did fit the other way around , they would still move the air in the same direction...
John ;-)
John ;-)
-
- Minor Addict
- Posts: 667
- Joined: Sun Aug 27, 2017 6:05 pm
- Location: West Yorkshire
- MMOC Member: Yes
Re: Head gasket failure-3rd in 2½ years
Unless the fan was for a Mini, they run the opposite way
Phil P
Phil P
-
- Minor Legend
- Posts: 1666
- Joined: Thu May 12, 2016 6:33 am
- MMOC Member: No
-
- Minor Fan
- Posts: 158
- Joined: Fri Mar 30, 2018 1:21 pm
- MMOC Member: No
Re: Head gasket failure-3rd in 2½ years
Ref the worry about running cool, is the temp gauge pick-up in the radiator or in the block? If in radiator, cool running is not unexpected. If in block, the temperature (once fully warmed up), should remain fairly close to the thermostat's specified temperature. If it's a lot cooler than that, then something may be amiss.
- ndevans
- Minor Legend
- Posts: 1088
- Joined: Fri Mar 03, 2006 11:56 am
- Location: Bristol, England
- MMOC Member: Yes
Re: Head gasket failure-3rd in 2½ years
The gauge sender is in the head. It screws into the head just under & to the rear of the thermostat. I have tested it out of the head, as described above, and it seemed fairly accurate set against a thermometer.
-
- Minor Legend
- Posts: 1666
- Joined: Thu May 12, 2016 6:33 am
- MMOC Member: No
Re: Head gasket failure-3rd in 2½ years
but I am slightly concerned that the gauge is now not going over 160°F, as if that is correct, the thermostat wouldn't be opening.
Just read back a bit on this thread, to the post with the above quote.
Surely you have checked your thermostat, after making sure the facts are correct? If thermostat is an 88 Celsius surely it is far more likely that, if the temperatures are to be believed, it would indicate the thermostat is not actually closing. Have you checked? Simple enough, I would have thought, to do that before posting?
Just read back a bit on this thread, to the post with the above quote.
Surely you have checked your thermostat, after making sure the facts are correct? If thermostat is an 88 Celsius surely it is far more likely that, if the temperatures are to be believed, it would indicate the thermostat is not actually closing. Have you checked? Simple enough, I would have thought, to do that before posting?
- ndevans
- Minor Legend
- Posts: 1088
- Joined: Fri Mar 03, 2006 11:56 am
- Location: Bristol, England
- MMOC Member: Yes
Re: Head gasket failure-3rd in 2½ years
Have you read the post above?