posted by
someone claiming to be Mike
on
Mon Feb 12 15:05 CST 2024 [RELATED]
1980 Volvo 245 M46
Temp Guage normally at 9 O'Clock. Started climbing to 3/4 before red - shut off - replaced thermostat - same problem. Car did not get near the red since I shut it down well before that.
But there is fluid, but the top rad has and radiator are cold - bottom os warm.
Sound like water pump?
GMB, HEPU or Original Volvo the way to go. May as well do rad - as it's a 5 yr old Nissan's.
Thanks for the advice and your experience with pump manufacturers.
For temp sender, voltage stabilizer and gauge testing and replacement in the early 240s, refer to pp. 53-60 in TP11402 Electrical Systems and Instruments Repairs and Maintenenace 1976-
You'll need to source a test resistor of the specified ohms and tolerance or accurately set an appropriate pot, maybe adjust the gauge horizontal with it and re-measure the pot. The test resistor specified says to 1976, but will be the same as yours. All VDO clusters to 1980 apparently used the same voltage stabilizer, not used in the Yasaki's.
My own thoughts:
You've pretty much confirmed the voltage stabilizer has issues what with corrosion. Look at the pic in the manual to see how low the temp needle goes when off.
Are you sure your fuel gauge is reading normally? The gauge may peg high before the tank is actually full if the stabilizer is wonky, so maybe fill up slowly with the gauge on and pause occasionally to watch its progress. Generally, just above the 9 o'clock half full mark should be pretty close to half the tank capacity spec if you tippy-top up.
At warm idle, do the gauges move significantly when the headlights and blower on high are switched on/off? ->Stabilizer unless your alternator regulator and/or battery are shot
--
Dave -still with 940's, prev 740/240/140/120 You'd think I'd have learned by now
posted by
someone claiming to be Mike
on
Thu Mar 7 18:41 CST 2024 [RELATED]
Replaced the coolant temp sensor with a FAE brand aftermarket #460191. On start up can't see the temp needle it is too low and hidden from view. After a drive it rises to about the 8:30 position. It is not overheating and correct operating temp confirmed with infrared. Is stable unless I do the following.
If I put any electrical load on - headlights/blower - the needle drops rapidly to about 7 O'clock.
Also if I select heat by itself (blower off/headlights off) - it also does the same thing . If heat shutoff or blower or headlights shut off it rises back to 8:30 again and is stable. Fuel gauge is stable and does not change during all of this.
It's a 1980 Volvo 245 with a VDO cluster so does not have a temp compensating board.
Any ideas. Voltage regulator, grounds?
Am thinking of replacing it with a 'genuine' Volvo sensor 460191 from FCP. Have read some posts on Turbobricks saying that the aftermarket one work on some models and not so well on others - despite what their manufacturer says. I just want an accurate reading obviously
Still glad to hear you are enjoying some progress with the readings and know that you are not overheating.
I having a real problem with you saying you cannot see the temperature needle.
That doesn’t seem right at all.
The gauge might be fatigued. It can happen in a couple or three ways. 🙄😋
I have a 1984 and the needle sits right over the “C” below the operating zone.
I’m not able to look at my 1978 GT but I’m pretty sure VDO manufactured both fuel and temperature gauges for all the 240 years.
That is at least up to the electronic versions .
Speedometers are cable driven versions from 1984 and back. Maybe even to the beginning Volvo making cars.
When it comes to instrumentation on all these gauges have to use voltage regulation.
as they are heating elements in them. They like a steady voltage/current relationship.
This power regulation is set between 9 to 10 volts in the units with the advent of 12 volt systems world wide. This way no matter how low the battery get or current draws from elsewhere will it affect the reading substantially.
On extremely hot or cold days the needle’s location will vary only slightly.
You can see it on the engines temperature more noticeably.
You probably think it’s because the radiator is doing more or less work but it’s the gauges element.
The reason is the regulator and gauges are in essence heating elements, just like a light bulb.
In fact, the old Volkswagen bugs used one to regulate current to their fuel gauge.
If the light burned out, that causes a loss of current to the gauge, it said empty all the time.
If you didn’t have a working gauge you probably wouldn’t have a very bright instrument panel at night.
I never drove one at night to know.
Nowadays on our speedometers they are using a solid state transistor that chops or pluses to ground.
Some are called Zener diodes in other circuits. On bugs, if you cannot get the bulb, as it’s in a case with an hole, any longer, then what you have to wire one in place of it.
I suspect a substitution is possible off a later speedometer. But that would take someone else’s opinion or knowledge on this board to answer that question. Hello Art Benstein!
As answer to your question, “ Any ideas?
Voltage regulator, grounds?
Gauge fatigue as above, makes three.
If the fuel gauge, if accurate (?) that has been discussed, would point again to the temperature gauge.
Most Anything that’s drooping out of sight surely has an explanation.
🤭 Is your car named a he or she by chance? 🤭
I would suggest that if you see any there’s a lot more.
The heating element may be harboring more under itself and that may contribute to less heat transfer into the bimetal finger.
The heating coils fine wires may also be compromised.
If it is working correctly there should be a pulsing voltage on the circuit board to the gauges of which may be hard to interpret while using a slow response digital voltmeter but not the less it must stay constant to be able keep the level even to the gauges.
It is current delivery that as important as we are talking wattages here.
What I don’t understand is how the temperature gauge is being effect more that the fuel gauge.
The temperature gauge with its needle out of sight makes me think it is more of a gauge problem and not the voltage stabilizer.
Corrosion is a big green gremlin here.
I wish you had another one for comparison or rig up that bad one to a variable resistive circuit and check the specs. On the temperature one or the fuel gauge there must some charts somewhere in manuals.
The voltage stabilizer comes with a steel enclose where the gauges are out in the open environment from the face of the dash. These were not built like the rectangular or even the round clocks as auxiliary option in Volvos.
Especially when turbo cars were built to be the new eye candy for Volvos.
A lot of the automotive industry had changed to what they call today to be a combination style cluster but Volvo liked what they liked.
They were selling their modest share of vehicles so use just don’t knock success as long as profits are reasonable and greed wasn’t so much of a factor in the business.
The sedans hand a long run and still have a good fan base due to common sense car building.
" top rad has and radiator are cold - bottom os warm. "
Three year old Nissans radiator with the metal or the plastic side tanks?
If you used 50/50 premix, there may you may not have an issue with the radiator.
If you mixed antifreeze with water, you use at least distilled or best, deionized water.
If you used tap water, the minerals precipitate out of the coolant clogging the radiator and heater core from the lowest level horizontal tube upward.
Your location and water treatment to make potable water will have an effect on the rate of clogging the fluid to air heat exchangers radiator, heater core).
If an all-metal radiator, you can use a radiator service to 'boil out' the precipitate inside the radiator. With the radiator safely drained and recycled, remove it and use sun or a spot light and peer into the large bottom radiator hose port. The horizontal tube ends will have an off-white material clogging the end.
Ensure a new thermostat is installed in correct orientation. Wahler (Borg Warner) Vernet make quanily thermostats.
On the Volvo OEM water pump gasket I use silicone grease and thoroughly baste the gasket so it darkens and swells and slides as you lever up the water pump to compress the top seal. Also inspect the steel tube end for the coolant return for corrosion or may not seal well on the small ring gasket.
Verify all coolant carrying hoses are recent. Unsure how old they can be.
As for coolant, maybe 24o can use organic acid technology, as Arty B. mentioned before. Else, phosphorus-free green prestone, the usual collection of quality blue coolant (Xerex G-05, I forget now.). I use Walmart distilled water and a gallon of antifreeze. Pour in all antifreeze and fill with distilled or (more $$) deionized water.
Bear in the mind the trick with the 240 water pump where you lever up the water pump to compress the top sealing ring or gasket. Use Volvo OEM gaskets. If the block surface is without pitting or other sealing issue causing defects
Inspect the thermostat housing interior. That housing is an aluminium alloy that is the least noble allor in the system so when coolant protection fails the metal inside that house cavitates to form at least pits and worse. Next is the cylinder head water jacket interior.
So, in the FAQ, among the best resources for 700-900 owners anywhere, and replicated on other sites, has information you can use. Same engine under that hood as is on 900-700.
And I hope your brake fluid reservoir is not back and is clear or honey color.
-- Give your brickboard.com a big thumbs up! Way up! - Roger Ebert & Gene Siskel
posted by
someone claiming to be Mike
on
Fri Feb 23 05:28 CST 2024 [RELATED]
I changed the water pump - good results no leaks - thermostat is new - Vernet 87C and opens in boiling water test. Filled engine 1st thru thermostat opening with 50/50 -then thru reservoir tank - new hoses - installed thermostat with nipple at 12 o'clock.
Ran car after 10 minutes got OK heat with heat on full blower on low - but as temp gauge reaches 9 o'clock the top rad hose is still cold and feels empty - so thermostat not opening/air lock in engine or thermostat housing?? So massaging the top hose does nothing if thermostat closed. What is the best way to purge air out of block? Crack the housing a bit with cold engine running to bleed any air out and confirm pump circulating? Or should a head gasket be considered. I shut car down with gauge at 75% so never got near red.
No coolant loss
(I have another 240 and the top hose starts getting warm at the 9 o'clock position).
Over all car runs well when warmed up - some white smoke at start up which goes away after 10 minutes - oil cap has a tinge of white but goes away after a longer drive - I live in a humid area so possible humidity trapped in a cold block - oil is not creamy looking.
Only thing I have not changed is the rad - but could be a moot point if air in block and thermostat not opening.
BTW what is a fair head gasket replacement cost these days on a 240 - am told its relatively easy compared to todays more 'complex' cars.
Am taking it to the shop soon for a diagnostic and pressure test. Thanks for the tips.
I once had an odd air lock somewhere in the block after a full drain and doing the heater valve hoses, but not as stubborn as that. I'd first try a bit harder to force out any remaining trapped air. You need to massage the lower hose to force coolant both through the block and up through the rad core. The upper hose mostly just pushes air out of the hose and into the top of the rad. Remove the rad cap (so no pressure builds up), fully warm the engine (gauge at or above 9 o-clock) then shut the engine off. The thermostat in theory is now open if there's coolant present. Massage the lower rad hose (use two hands for maximum compression, caution not to do this too suddenly so you don't blurp coolant out of the open reservoir) then massage one hand lower hose, one hand upper hose, alternating like a pump to move coolant through the block. Note if trapped air now bubbles into the reservoir and the upper hose now becomes warm with a feel of fluid in it. Push the block end of the upper hose down a bit below level to maximize air removal. Do with the heater control fully open then repeat the massage with the heater control fully closed. If you're parked on a slope, best to do this with the front end high. Top up as needed (knowing that air is being removed). Replace the rad cap and re-test for the upper hose to now become hot and confirming the thermostat is fully opening. If needed and still not opening, repeat the massage once more before giving up.
Question 1, the thermostat is installed with the crown up, the spring down into the block, and turned with the weep hole up high, correct?
Question 2, were you previously losing coolant and needing to top up more frequently? Mystery coolant loss can be the beginnings of head gasket failure. You may not notice discoloured or oily coolant. If there's a head gasket leak into the cooling system, one good test is simply to run the engine with the rad cap off. You should be able to idle almost indefinitely with the rad cap off if coolant is moving through the rad. Fluid will rise, but if you all of a sudden have an eruption then it's a head gasket. You can run it above 9 o'clock on the gauge, just stop when it hits the red. These red blocks engines can take a lot of abuse so even being in the red for a short time is no problem.
Question 3, you're not in sub-freezing weather, are you? Warm up can take considerably longer. BTW, in cooler weather, white steam from condensation in 240 exhaust systems with the large rear muffler across way at the back end can go on for many miles until it finally gets hot. One of the reasons 240 and 140 rear mufflers and pipes rot out faster if all you do is short trips, especially if you park outdoors overnight.
--
Dave -still with 940's, prev 740/240/140/120 You'd think I'd have learned by now
posted by
someone claiming to be Mike
on
Wed Feb 28 04:57 CST 2024 [RELATED]
Took it in for a complete diagnostic.
After start up, temp needle started to rise after a few minutes. After 5 minutes at 9 o'clock - and rising fast.
Shut it down at the mechanics shop at 75%.
They ran it for half an hour and I was panicking but with their thermal scanner it was moving fluid and temp of engine was normal - so it is the coolant temp sensor that was fooling me - I was shutting it down early because I was seeing an overheat coming before the thermostat opened to circulate fluid.
So will replace the sensor and keep you posted. Just have to soak the area in penetrating oil for a week to unseize it.
So in retrospect - when it starts to warm up faster then normal based on the gauge (false indication) that is an important clue. Thanks again.
Glad to see you got a thermal consensus, like I suggested in my earlier post and I will leave it that.
Shame you don’t own that thermal tool that you just paid for.
They are good for checking refrigerators, freezers and calibration of cooking ovens when using an iron skillet.
The list continues on but experimentation on some objects is required.
You will gain some understanding of things are physically with density versus liquids and gases.
I’m in a comfy armchair and it was very hard to see what you were seeing and all the members were having the same dilemma.
Like Art B. was with the voltage regulator by giving you a best guesses from his experience.
How full or empty is a gas tank really? 🤔
I suspect the orange reserve space is equivalent to about two gallons or up to fifty miles but do even trust that is the best advice due to **** Happens!
I was really having a problem with a new five year old radiator being plugged up so soon.
Your makeup water for coolant mixtures would have to be almost liquid rocks to do one in that quickly.
The suggestions brought forth in your thread are very helpful tips of how many ways things can be misleading while meant as good intentions to help.
Welcome to the Brickboard and to the wonders of civilization an inventions.
I love it that you kept us posted!
You wouldn't have to pre-treat the voltage stabilizer to swap it out. Anyhow, if the gauge sender doesn't make it read right, consider it may be that mechanical voltage stabilizer. They tend to fail shorted, sending a constant battery to the gauge (13.6V).
They can't be verified just by measuring the voltage, because they regulate by cycling the battery to the gauge unlike the solid state stabilizers that provide stable 10V. However, you should be able to see it cycling with a meter if you are patient.
--
Art Benstein near Baltimore
How come nothing rhymes with orange?
What? Nothing doesn’t rhyme with orange?
posted by
someone claiming to be Mike
on
Thu Mar 7 11:42 CST 2024 [RELATED]
Thanks for the info. Just had the sensor in the head replaced - not overheating - it was apparently a false signal.
However here is what it is now doing.
When I shut down the needle drop well below C and I can't even see it except if I look to the side.
As it warms up it stabilizes at 9 O'clock and stays there - until I select heat and turn the fan on then it drops to 25% - between C and 9 O'clock (happens immediately) - so likely an electrical thing. When I turn heater blower off it goes back to 8:30-9 O'clock.And when idling needle wanders mostly downward and looks jumpy 'sticky' Erratic.
Where and what should I look for next ?
Much appreciated. At least I know it's not overheating.
From under the hood, you can verify the operation of the voltage stabilizer that keeps the fuel and temp gauges accurate. For those with 1981 and later 240s, checking the voltage at the end of the yellow wire pulled from the temp sender in the head, it is simple. Expect 10 volts.
The mechanical stabilizer used in the earlier cars operates like the old turn signal relays, using a bi-metal strip heated by nichrome wire, and like those old relays, tends to fail in the closed-circuit (shorted) position. This will make the gauges, both fuel and temp error to the high side.
Checking with a test light (use a small one) will reveal the battery voltage is interrupted fairly rapidly. Because the gauges are thermally operated, the rapid fluctuations are not seen in needle movement. Checking with a digital voltmeter makes it look like the stabilizer voltage is anything but, when it is working properly.
Getting a clip lead on it...
--
Art Benstein near Baltimore
Did you hear about the kidnapping at school?
It’s fine, he woke up.
posted by
someone claiming to be Mike
on
Sun Feb 25 11:05 CST 2024 [RELATED]
Great instructions - followed to a T.
Removed Calorstat 88 thermostat and tested open as specified - installed with vent 12 o'clock car on ramps and topped up block with 50/50. Cleaned temp gauge sensor too.
Once gauge at 9 o'clock getting heat and heater pipe under exhaust manifold hot - massaged hoses with cap off - top hose got warm but bottom cold - shut off for 2 minutes and did again - no change.
With car off can feel fluid in top hose very little in lower.
Did you inspect the radiator cooling fins for gunk that might clog them? Consider using a garden hose with a sprayer and carefully spray the fins from the REAR to clean them out. It is worth a try. No cost…
Head gasket: If the white smoke goes away quickly then it is probably just condensation due to cold weather. Instead, try sniffing your exhaust for a sweet smell when it’s warmed up.
Has the temperature compensation board been removed from this car's cluster?? That would be the first suspect in the symptoms you refer to.
Art has provided instructions for the procedure: https://cleanflametrap.com/tempFaker.html
EDIT: That Nissan radiator will be good for years to come if it is only five years old.
I am of the opinion that HEPU water pumps score high on both quality and price when searching for a replacement. However, I suggest the first thing you do in your case is remove the temperature compensation board.
--
Any twenty minute job is just a broken bolt away from a three day ordeal
I appreciate the plug, but we haven't been selecting the year in the model/year dropdown much on this board. 1980 according to the first post. No temp comp circuitry.
Jarrod's model/year question is one thing that separates the Brickboard from the pre-packaged forum apps. I think it really goes a long way to keeping us on track when reading. I had to do a check whether the year was mentioned, by re-reading.
Another electrical thing about the 1980 is the use of a mechanical voltage stabilizer for the gauges. By '80 it should have been the solid state one inside the same old can, but who knows the history of the cluster repairs.
Close-up from a rally cluster"
OK, here. The first is the back of the stabilizer. Next, the usual mechanical stabilizer using heated bimetal, and finally, a replacement unit with a 10-volt regulator chip inside.
--
Art Benstein near Baltimore
"Well, here we are, Mr. Pilgrim, trapped in the amber of this moment. There is no why." -KV
posted by
someone claiming to be Mike
on
Mon Mar 11 11:16 CST 2024 [RELATED]
Thanks ART - yes this is what I have - the windings in the bimetallic are corroded off. How do I replace with a solid state one like you have. I am OK at soldering but am unsure where the 3 pins of the chip go to with reference to the 3 connectors on the old one.
So thanks for some more detail. Much appreciated. Mike
I won't make any excuses for myself. I thought it was very odd that someone hadn't pointed out the symptoms matching up with the compensation board being in place.
--
Any twenty minute job is just a broken bolt away from a three day ordeal
posted by
someone claiming to be Mike
on
Thu Feb 15 15:37 CST 2024 [RELATED]
It's a 1980 so don't think it has a compensation board. Am going to change the water pump - squeals on start up - anything to look for as far as debris from impeller getting into the coolant system - backwash/flush the system and rad?
A squeal at cold start is often a drive belt, but could be the pump. The impellers are metal, either cast or stamped, and don't disintegrate, so no bits to really worry about. I'm not sure why others got caught up on the temp compensation board. Your symptoms of a cold top rad and warm bottom rad were consistent with pump failure as long as the engine was allowed to warm sufficiently to open the thermostat, plus yours is an early 240. Still, could be a gauge problem if it's just a loose belt.
--
Dave -still with 940's, prev 740/240/140/120 You'd think I'd have learned by now
The temperature compensation board AKA “temp faker” started in the 86 models. Clogged radiator fins can cause the OP’s symptoms. The radiator fins can be cleaned if they aren’t too brittle.
I want to say be suspicious of the sending unit or the wiring to the gauge may be going to ground in like a frayed wire inside the harness.
That wire can get powered or be grounded through another source.
The top hose and the radiator itself should be hotter at the top as heat rises and the water is less dense.
The bottom of the radiator should be cooler as it loses heat and the water cools. It goes downward by natural convection.
So with that there is a conviction about a dead pump or sensor and or gauge.
You really have an infrared thermometer for occasions like this
They are also handy for reading brake disc and a myriad of other things besides a car.
Just saying both conditions of a spun pump impeller or a wiring issue comes towards you as being uniquely rare.
Good idea to replace the radiator too. Sounds like it could be clogged. My 90 240 ran 3/4’s of the way to red when in traffic as the OE radiator was slowly clogging up and on its last legs… Like yours, top was cold bottom hot.
I don't see others jumping on board here, so yes, likely as anything the water pump. If it wasn't leaking coolant or the bushing screaming then maybe the impeller is slipping on the shaft.
The general consensus in the old Volvo community is that the Hepu pump is the most reliable replacement for the money. The Hepu has a cast impeller, while the GMB is a stamped impeller. In theory, a bladed stamped impellor could be more flow efficient, but the pressed attachment may be less reliable to stay attached on the shaft. Way back, reportedly the GMB impellers could occasionally separate off the shaft, but I've not heard of that in recent years. I note the most recent version of the Volvo pump also appears to now have a stamped impeller with blades, aleit it with a more solid looking center.
In the past I've used a number of both GMB and Hepu pumps with okay results and given a choice would choose Hepu. Rockauto doesn't carry Hepu at the moment, but does have the GMB at a very affordable price, so FCPEuro with their lifetime guarantee for the Hepu would be my preferred choice, although Eeuroparts has the Hepu for slightly less at the moment. The Genuine Volvo is simply not worth double the money.
There have been recent comments here about the rough casting quality of the Hepu pumps compared to the Hepus way back. It's hard to imagine a leak developing with a properly clamped hose and a proper fibre gasket (not just a thin paper gasket). No gasket sealer is called for by Volvo other than a wipe of petroleum jelly on the top of the upper mushroom rubber gasket so it doesn't fold over in final positioning. I use a hylomar-type, completely non-drying gasket sealer on the block gasket for a guaranteed seal and more importantly so the pump can be removed and re-positioned as needed later without needing a new gasket. Doing this, I've been able to remove and reseal the upper gasket when needed without having to replace the main gasket. The main thing is to force the pump up high under the head flange for final tightening and as an added bonus to put a wipe of RTV sealant into the crack between the head flange and the pump to keep valve cover oil leaks and spills from getting onto and softening the upper mushroom gasket.
--
Dave -still with 940's, prev 740/240/140/120 You'd think I'd have learned by now
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