What oil temp Temperature gauge do I trust, Just installed the new Pressure & CHT guages Options

[jc914]

I just finished cleaning all the inside glass of all my gauges (what a difference they look NEW) So I toke her out in the Miami weather tonight the outside temp was a nice hot 80 degrees. I drove my 914 for over an Hour an Half I drove her really hard and fast up 80MPH:driving: . The OEM temp gauge only read a 1/4 up and it never even got half way up (IMG:style_emoticons/default/piratenanner.gif) . Once I got home I opened the engine lid and the Dip stick Temp Gauge read 250 degrees. ( note i have checked the dip stick boiling point yesturday before i installed it.) If My 914 is running hot what what might be the causes and which gauge should i trust. (IMG:style_emoticons/default/devil.gif) (IMG:style_emoticons/default/confused24.gif) (IMG:style_emoticons/default/confused24.gif) (IMG:style_emoticons/default/confused24.gif) (IMG:style_emoticons/default/confused24.gif)

The car idled at 1 the whole night when i got home i turned her of and then on again after like 5 minutes and it started with some gas on the peddle.

thanks
JC

[Dave_Darling]

Check the dipstick gauge against boiling water. That'll tell you if it is trustworthy...

--DD

[jc914]

Thank DD i had already done that before I installed the dip stick. is 250 degrees to hot
JC

[Ferg]

I'd wager that you have the stock gauge with the bigger red zone... if so it was most likely reading correct.

Trust the dipstick gauge, I have used one since they were available and it opened my eyes as to how hot stock cars run. I'm not surprised you saw 250.

Too hot? Most likely, head temps ect all come into play, but in the end, I'm a believer that second cooler is a smart thing. You may be able to get the temps down with tuning ect, but I think they all run warmer than owners want to believe.

Ferg

[Gint]

i have checked the dip stick boiling point yesturday before i installed it.

You pretty much answered your own question right there. You don't have a clue what the stock gauge actually reads, but at least the dipstick gauge is calibrated (more or less).

[jc914]

Thanks for helping (IMG:style_emoticons/default/beerchug.gif) (IMG:style_emoticons/default/mueba.gif) . I am going to give the car a full tune up next month. I hope this will bring down the temp. I am also going to buy a CHT gauge. Most likely the VDO I know the are not temp compensated but for the price I rather do the math to compensate the temp. I also want to keep my gauges looking the same.
JC

[jim_hoyland]

Ferg is right; the dip stick gauge is pretty accurate. I used one to verify my sender and gauge were properly matched.

If thesender is in question, you can remove it from the case and did it into boiling water. That will tell you where 200-212 is on that gauge. If you pull the sender, be sure to use a new crush washer when it's replaced.

[Ferg]

For those who are wondering what a dip stick gauge is, I'll throw out a free plug for the vendor as he is a good one...

http://www.mainelycustombydesign.com/engin...s.html#dipstick

Also it reads temp right where the stock sender does, (if' you've ever had the temp sender plate off you can see the bottom of the dipstick) so the temp readings are taken from the same location.

I used the dipstick gauge to give me real time readings from the stock gauge in the car... After a few drives and stopping to check the dipstick gauge, you can see where the stock gauge is, and get a idea of what the non numbered gauge is telling you.

One warning though, it will make you nervous, as I could not believe how hot "normal" was on the stock gauge. Straight up and down, on the gauge with the small red zone is right about 215, if the needle is touching the "M" on the word TEMP you are 235-240ish and if you are on the P it's 250 and above, all below the red zone.


Ferg

[ericread]

Thanks for helping (IMG:style_emoticons/default/beerchug.gif) (IMG:style_emoticons/default/mueba.gif) . I am going to give the car a full tune up next month. I hope this will bring down the temp. I am also going to buy a CHT gauge. Most likely the VDO I know the are not temp compensated but for the price I rather do the math to compensate the temp. I also want to keep my gauges looking the same.
JC

You are on the correct path. Who cares what the oil temperature is telling you? By the time the oil temp is recorded at the high point, it's proably going to be too late to save your engine. The important measurement is the CHT. I purchased a compensating CHT, cylinder probe and wiring for under $100.00 at Aircraft Spruce. In the past couple of months, I find that my oil temp gauge matches up to the CHT gauge reading- after about an hour. As for temp cool down, the oil temp gauge provides no real help. If you're worried about your engine temp, go for the compensating CHT.

Eric Read

[jc914]

Ferg thanks for the great information on the gauge. One more question I just replaced the wire from the temp sender to the engine bay conector when o got my above reading . Would the length of the wire changed the temp reading.

JC

[Ferg]

Ferg thanks for the great information on the gauge. One more question I just replaced the wire from the temp sender to the engine bay conector when o got my above reading . Would the length of the wire changed the temp reading.

JC

I don't think so, but someone will correct me if I'm wrong.

Do you have the stock gauge with the big red zone starting just past midway, or the later with the small red on the far right... My findings are from the later gauge, I've never owned a car with the "big red zone" gauge.

Ferg

[jc914]

I have the one with the BIG red zone. Thanks

JC

[type47]

i have the dipstick gauge installed in my 1.8 and the highest temp i've observed is 210F.

[jc914]

I just toke her out for another ride of about forty five minutes stopping and looking at the temp on the dip stick it ranged from 220-250 250 being the max i got and no matter how hard i would drive it would it did not go any hire than 250. Tomorrow i am going to clean the oil cooler with brake cleaner, check the fan and make sure there is nothing blocking it and later in the week i am going to do an oil change ( have to admit the oil is really old like 4 years only have ran like 1,000 miles I know shame on me (IMG:style_emoticons/default/headbang.gif) (IMG:style_emoticons/default/chair.gif) (IMG:style_emoticons/default/behead.gif) ) I hope this will bring done the temp at least to 220 at its highest point.

I have been looking at the CHT i think i am going to change my mind and go with the Dakota I just cannot see my self driving looking at the gauge and doing some math in my head to get the CHT degree from the VDO

For those of you that have a temp gauge with the big red zone this is what I used on the stock gauge to correlate to the dip stick gauge. When the top of the needle passed the top Tip left of the T (on the temp word) i had 220 from the dip stick. When the needle got to almost the tip of the end of the T i had 250 on the dip stick.

[Ferg]

I'm not trying to be a downer, but I speak from some experiance, as I've had a few 914's...

220 as a high point in your climate and highway driving is very optomistic without a second cooler, and impossible in the summer.

I'm hoping you find blockage (check your warm up flaps too) but the temps you are seeing are exactly what I have seen with all my 2.0's before a aux cooler.

Ferg

[jc914]

FERG Thanks for your honesty I am considering a second cooler where can i buy one I am really thinking about it

JC

[Gint]

I'm not trying to be a downer, but I speak from some experiance, as I've had a few 914's...

220 as a high point in your climate and highway driving is very optomistic without a second cooler, and impossible in the summer.

I'm hoping you find blockage (check your warm up flaps too) but the temps you are seeing are exactly what I have seen with all my 2.0's before a aux cooler.

Ferg

Bah! Hot-schmot!

My /4 has no temp gauge of any kind. I borrowed Ferg's Mainley dipstick thermo once. Saw 230-240. "That's a little high." Pulled that sucker out and gave it back to Ferg. Twisted the key and dumped the clutch and throttle and never looked back. (IMG:style_emoticons/default/driving.gif)

That was a year or so ago (maybe more?). When if it breaks I'll fix it.

Drive it like you stole it!

[Ferg]

I'm not trying to be a downer, but I speak from some experiance, as I've had a few 914's...

220 as a high point in your climate and highway driving is very optomistic without a second cooler, and impossible in the summer.

I'm hoping you find blockage (check your warm up flaps too) but the temps you are seeing are exactly what I have seen with all my 2.0's before a aux cooler.

Ferg

Bah! Hot-schmot!

My /4 has no temp gauge of any kind. I borrowed Ferg's Mainley dipstick thermo once. Saw 230-240. "That's a little high." Pulled that sucker out and gave it back to Ferg. Twisted the key and dumped the clutch and throttle and never looked back. (IMG:style_emoticons/default/driving.gif)

That was a year or so ago (maybe more?). When if it breaks I'll fix it.

Drive it like you stole it!

(IMG:style_emoticons/default/poke.gif) spend a week and drive up I70 and get back to me (IMG:style_emoticons/default/laugh.gif)

Your results may vary. (IMG:style_emoticons/default/popcorn[1].gif)

Ferg

[jc914]

OK I will THANKS AGAIN FERG

JC

[ericread]

220 as a high point in your climate and highway driving is very optomistic without a second cooler, and impossible in the summer.

I'm hoping you find blockage (check your warm up flaps too) but the temps you are seeing are exactly what I have seen with all my 2.0's before a aux cooler.

Ferg

When you get your CHT installed, you will probably begin to see real engine temps - please see Jake Raby's article for reference:

http://www.914world.com/specs/JakeRabyHeadTemps.php

Eric Read