Oil Gauge 87 gt (Page 2/3)
jon m NOV 24, 02:40 PM
Hi - Many thanks for your replies so far.
As a matter of course and as the weather is cold - I am drainging the 10w 40 oil out and changing the filter and putting in 5w30.

on another note I am going to look at the plug - I did change out to the 88 sender but kept the original plug and put the new pig tail wiring into it so connections may have become dirty

quick question - does anyone knows what is the torque in nm for the drain plug ?
will hopefully update soon
Jon

[This message has been edited by jon m (edited 11-24-2022).]

Xenoblast NOV 24, 04:18 PM
https://images.fiero.nl/2017/torque_specs.jpg
greenturnedblue NOV 24, 06:51 PM

quote
Originally posted by jon m:
I did change out to the 88 sender but kept the original plug and put the new pig tail wiring into it so connections may have become dirty




You can easily test this by probing the wires before and after the pigtail with a multimeter -- resistance should be '0' or extremely low. If not, the connection is weak
theogre NOV 24, 07:09 PM
Oil plug torque spec is good but often the pan and/or plug has damage and tighten to spec can fail.

Many pan holes are so damage in different ways you need nylon seal etc so crushes around the damage.

So many time you just tighten to seal and hold w/o stripping the iffy threads.
If threads strip in the hole, you have to deal w/ finding oversize plugs or other repair... That if the car doesn't have double oversize plug already.

Example: 1 old pan I have the plug had wrong size aluminum seal and crush the pan to "countersink" the hole.
The plug only have big part of head to seal with a nylon "gasket."
Patrick NOV 24, 09:36 PM

quote
Originally posted by jon m:

quick question - does anyone knows what is the torque in nm for the drain plug ?



You want a torque reading... for an oil drain plug.... in nm no less??!!!

Just yanking your chain Jon, but I'll give you some "torque" advice that was offered to me 50 years ago when I was 16 years old at my first job.

If you look at a flat wrench set, you'll notice that the smaller sizes are shorter in length than the larger sizes. The longer the handle, the greater the leverage, and the more you can tighten a nut/bolt. It's therefore pretty difficult for example to over-tighten a 7/16" nut with a six inch long wrench. And as long as you're using an appropriate length handle on a socket wrench, you'll usually be okay. In other words, don't start reefing on that same 7/16" nut using a 3/4" drive ratchet (or bar) with a two and a half foot long handle. For an oil drain plug, I'd either use the proper size box-end wrench, or the proper size socket with a 1/4" drive ratchet (or 3/8" drive if you're gentle).... and just snug it. It's not a head bolt!

[This message has been edited by Patrick (edited 11-24-2022).]

jon m NOV 25, 10:54 AM
Thanks for your replies so far - Patrick Hope you have been keeping well long time no chatter on here for me.

Right so far - Changed the oil out for Shell 7hx 5w30 which is part mineral / part synthetic and the filter as well.
Put 4 quarts of the oil in so will probably need to top up (bear this in mind for the result so far)
Started the car up and let it idle to near warm (again time was against me until tomorrow)

Findings - The gauge went over to 80 but as the car got warmer it did start to drop and get to 60
When I turned the car off and put the key back over (not starting the car this time) The needle stayed just at the red zone on the left side
for a while before dropping back to 0 and the oil light coming on.

I will do an ohms test hopefully tomorrow just to check all in order

I have a couple of side note questions - what would happen say if I got the 2 fuel pump wires the wrong way round on the pig tail and the tick over on my fiero isnt smooth as a modern day car and fluctuates very slightly plus the exhaust manifols, Y pipe have been ported as well as a free flowing cat and exhaust muffler also have Rodnys low temp fan switch so the temperature does not go to half way on the gauges/

Jon
Would this have any affect on the operation of the car in respect of the readings ?
Patrick NOV 25, 03:52 PM

quote
Originally posted by jon m:

also have Rodnys low temp fan switch so the temperature does not go to half way on the gauges



Which of the two low temp fan switches of Rodney's do you have?

Of more importance, in regards to oil pressure when warm... What is the temperature rating of your thermostat?
jon m DEC 07, 07:00 AM

quote
Originally posted by Patrick:

Which of the two low temp fan switches of Rodney's do you have?

Of more importance, in regards to oil pressure when warm... What is the temperature rating of your thermostat?



Right I have a little time.
Took her out and after a while the temperature got up toabout 150 and pressure is around 50 which I think is ok (please let me know) and the gauge needle does not dance about

Now as Patrick has asked this is what I am thinking - I did change out the thermostat a few years ago (now bear in mind the car hasnt been driven for 5yrs as life got in the way) so from what I can remember I put a low temp thermostat in as the car was over heating now again which turned out to be a small leak (now fixed).

So with the weather in the UK dropping to an average of 3 degrees C I am thinking that the thermostat is opening up too quick and not allowing the engine to warm up enough to thin the oil - so I am going to find my old thermostat and put that back in.

Jon
theogre DEC 07, 11:47 AM
T-stat has little to do with Oil Temp. Unless have 160°F/71°C T-stat keeping the engine colder, the oil will get hot fast enough
But starting Oil Temp in low temp weather does take longer to heat and if you drive very short distance then may never heat up to normal op temp.
Is Why xW number of oil weight matters so much in cold weather. Plus thin oil prevents oil bypass valve to open in cold weather too. Many cars, not just Fiero, have the bypass valve in the engine. GM puts this in the engine at the filter port that most never see the top of it hidden in the hole in the engine. (Bypass opens when input and output PSI at the filter is > 7-10PSI cause by dirt block flow or thick oil going thru the filter media. Has Nothing to do w/ system total pressure.)

50psi is a bit high but nothing to worry about.
Again Dash Gauge often isn't very accurate as covered above.

right after you charge the oil, takes a bit of time to really get the thin oil to all parts but dash gauge should "see" the thin oil very quickly in cold weather.
Sender is between oil pump and oil filter in most cars and w/ a new filter you completely "flush" that section and other bigger oil paths too.
Valve Lifters and rest of valve train is where you get slow flushing because of how they work.

IOW After replacing oil and filter, not much of old oil still in the engine so you drive or idle more then a few minutes then engine should "flush" thicker oil and dilute to the thin oil.

80+PSI then many oil filters and other parts can have problems. Even w/ good filters w/ heavy bodies (the "can" and Flange to attach) the filter gaskets and other areas are not meant to handle high pressure and can leak to total fail w/o Warning.

[This message has been edited by theogre (edited 12-07-2022).]

Patrick DEC 07, 02:26 PM

quote
Originally posted by theogre:

T-stat has little to do with Oil Temp. Unless have 160°F/71°C T-stat keeping the engine colder...



And that's exactly why I brought it up, just in case an extra low temp thermostat had been installed (and with the weather being colder now this time of year).