Engine/Transmission undertray

[A1.6HPE]

Hello,
Can anyone describe/post pictures of the undertray that fits ahead of the engine? My car has the cover under the transmission tunnel and the "barg board" thing on the bulkhead but nothing closing the space between the sump and bulkhead. My interest in this is because I suspect that the transmission is overheating - the oil is frothy, even days after being stationary. Any comments welcome.

Leo

[Will]

...I can post a picture if I can dig the thing out, I have a spare. Fact is, it'll run fine without though. What are you running in the box?
-Will

[A1.6HPE]

Hello Will,
I'm using Esso 90 oil - can't remember the full name.
I noticed that the udnertray has featured here before and now Chad has a photo of it in his part list.
The problem arises when on Motorways and presumbaly there is heat build up in the transmission. Shifting gears becomes extremely difficult - presumably due to the frothing of the oil. If I add in cool oil the gear selection reverts to normal instantly. Due to the froth it is difficult to work out how much real oil is in there. Did about 150 miles yesterday, put in a litre, but the level was way over the top on the dip-stick. Tonight I'll drain the transmission and re-fill with fresh oil. It will be interesting to see what comes out.

I wasn't too sure how important the undertray is so I appreciate your comments. No need to bother with pictures due to Chad's one, but thaks anway.

What do you suggest for oil?

Leo

[Allen Lofland]

As WILL HAS STATED, the underbelly pan is not needed for trannie cooling normally, I drove mine for some time with out it on. As for the trannie oil. Try this...Drain the fluid and replace with the recommened amount in your manual, DO NOT trust you dipstick :( I have measured three different dip sticks so far in Scorpions :)
I am using redline MTL at the moment....DJ recommende 40 wt motor oil to me in the past. My manual calls for .44 US gallons or 3.3 lbs of AGIP F1 ROTRA 85 W 90
or Esso Motor Oil SAE 40
or Mobiloil 50
My Zagato has the same trani and I was gong to use 40 wt motor oil this winter but couldnot find any so I have 20/50 penzoil motor oil in it right now and it works fine. BUT I would recommend 40 wt for summer. or even the gear lubs if you have hot weather.
Hope this helps....

[PeterCoupe]

It may froth if there is to much oil. Happened with mine few years ago.

Peter

[A1.6HPE]

Gentlemen!
Thankyou for your excellent advice. Am keying this as the oil drains out of the transmission.
Decided that yes, probably the oil level was too high. Then checked the “How Long Is Yours?” postings. Next I went to La Bella Lancia (A1.6 HPE) and checked the oil level and dipstick. A1.6 HPE still has the factory oil in it and the level is about 10mm above the MAX line! Dipstick is the same dimensions as the Montecarlo one (130mm from tip to shoulder of rubber bung, 111mm from MAX to shoulder, 117 from MIN to shoulder). Next stop was the handbooks – Montecarlo (S2) and all FWD variants have the same capacity 1.8 litres/0.47 US Gals and specify draining from both plugs but filling only via the dipstick hole.

Next stop is to put oil in the Montecarlo transmission (after replacing both plugs then filling it in 50 ml steps.

I am in Scotland so if the undertray is not neccessary in the USA then it should be even less neccessary here.

I’ll be back!

Leo (of course I may still have the leak problem but another transmission is on its way to me)

[Tom McGaffigan]

Large changes in fluid level from cold to hot are caused by water getting into the oil. The water that is in the oil causes the oil to greatly expand as it heats up way more than due to temperature change alone. If the oil exceeds 100 degrees C you will see foaming also. Change the transaxle oil and recheck the level.
The "belly pan" on a scorpion / Montecarlo traps positive pressure in the entire engine compartment, forcing the air entering from the front duct out the rear grill. An easy way to check is to drive 70 MPH with the engine lid unlatched. The engine lid on a car with a belly pan will raise up and can be seen floating behind you in the rear view mirror. A car without a belly pan does not have sufficient airflow or pressure to lift the engine lid at this speed.
Tom McGaffigan

[Will]

Tom, do you mean REAR grill, (tail panel) or engine lid grill? In normal operation, I believe air goes IN the tail panel and OUT the engine lid. On my "to do" list is to run a better streamer-check of this with a camera in the engine compartment, but who has the time??
-Will

[A1.6HPE]

OK I drained and refilled the transmission.
500ml of oil did not register on the dipstick. 1 litre took the level to about 5mm below MIN. 1.5 litres took the level to about 2ml below MAX. 2 litres made it to about 10mm above MAX. I left plenty of time between top ups so that the level could settle over any internal baffles. Latterly I raised the rear quite high to aid any settling but back on the level the oil was still about 10mm above MAX so I pumped some oil out until the level was 5mm above MAX. Off to a show about 30 miles from home so fingers crossed!

On the second production cars the air intake comes from the rear lights panel so that suggests that the airflow/pressure situation is such that airflow goes inwards.

Ciao for now, Leo

[A1.6HPE]

I made it safely to and from the show and loat about 2mm of oil doing so. Good news is no froth so it looks like I had overfilled previously.
Thanks for your words of wisdom. Hope to get replacemnt transmission on Friday so can swap at the weekend.
Is it easy enough to get the transmission out and leave the engine place?

Ciao for now, Leo

[Wallace]

Personally - I take the engine out when replacing the box. But then, I've B* all room in the garage !

I think you have to take out the gearbox side suspension to do it - then try and shift the box sideways and somewhow drop/pull it out . .. . personally - I think the engine out way is a lot easier. Especially when trying to line the splines on the clutch up when bolting it all back together. Can just be done in a day (that's how long it took me .. . .).

[Tom McGaffigan]

Will,
I was refering to the rear grill, not the openings in the engine compartment lid. I assume there is lower pressure at the rear of the car as well as lower pressure above the engine compartment lid than inside the engine compartment when the belly pan is installed. Without the belly pan installed the engine compartment lid does not lift at 70 MPH.
Tom McGaffigan

[Will]

Well... I thought so too, Tom, but a preliminary test I did suggested that the air flows IN to the engine compartment from the tail light grill, rather than out. This is with no belly pan, mind you. I'd have to try it again a few times before I'd bet my life on it, and it surprised me as well, I had thought the air would flow out there too.

-Will

[A1.6HPE]

Hi guys,
As I said above, the S2 cars have the carburettor air intake at the rear grille so the air flow must go in the way. If it went out that would defeat the incoming supply for the carburettor. I wonder if I will notice a performance boost when I have the undertray fitted?

Leo

[Wallace]

I think the series 2 has the air intake on the back shelf so it can get hold of a supply of warm air from the exhaust. On the first turbocharged engine I built, I used the same air filter - which wasn't a good idea as it picked up a LOT of heat from the turbo. It ended up right at the back of the engine bay, next to the petrol filler hose.

IMHO, I would THINK that the air would leave from the rear plastic vents - but air does some funny thigs when in motion - sometimes not what you'd expect.

Couldn't someone with a working (!) monte or scorp settle this for once and for all by tieing a few short lengths (about 2" or so) of string around some of the plastic slats and taking it for a blast ? YThen if the string ends up INSIDE the engine bay, the air flows IN, if they end up outside, the air flows OUT !!

[A1.6HPE]

OK I'm up for tieing bits of string to the back of my car. Hope none of my friends see it though.

I have just replaced the transmission - the replacement one has a larger dipstick hole and the dipstick markings are higher up than the original unit. This ties in with my HPEW having the oil level much higher than the MAX mark. It seems as if the S2 Montecarlo spec is for less oil but they ignored that and put in 2.5-ish litres. The "new" dipstick has a metal upper with an O ring seal whereas the previous one has a an all rubber upper. I'm confused on that amongst other things!

Leo

[A1.6HPE]

OK I'm up for tieing bits of string to the back of my car. Hope none of my friends see it though.

I have just replaced the transmission - the replacement one has a larger dipstick hole and the dipstick markings are higher up than the original unit. This ties in with my HPEW having the oil level much higher than the MAX mark. It seems as if the S2 Montecarlo spec is for less oil but they ignored that and put in 2.5-ish litres. The "new" dipstick has a metal upper with an O ring seal whereas the previous one has a an all rubber upper. I'm confused on that amongst other things!

Leo

[A1.6HPE]

OK I'm up for tieing bits of string to the back of my car. Hope none of my friends see it though.

I have just replaced the transmission - the replacement one has a larger dipstick hole and the dipstick markings are higher up than the original unit. This ties in with my HPEW having the oil level much higher than the MAX mark. It seems as if the S2 Montecarlo spec is for less oil but they ignored that and put in 2.5-ish litres. The "new" dipstick has a metal upper with an O ring seal whereas the previous one has a an all rubber upper. I'm confused on that amongst other things!

Leo

[A1.6HPE]

OK I'm up for tieing bits of string to the back of my car. Hope none of my friends see it though.

I have just replaced the transmission - the replacement one has a larger dipstick hole and the dipstick markings are higher up than the original unit. This ties in with my HPEW having the oil level much higher than the MAX mark. It seems as if the S2 Montecarlo spec is for less oil but they ignored that and put in 2.5-ish litres. The "new" dipstick has a metal upper with an O ring seal whereas the previous one has a an all rubber upper. I'm confused on that amongst other things!

Leo

[A1.6HPE]

OK I'm up for tieing bits of string to the back of my car. Hope none of my friends see it though.

I have just replaced the transmission - the replacement one has a larger dipstick hole and the dipstick markings are higher up than the original unit. This ties in with my HPEW having the oil level much higher than the MAX mark. It seems as if the S2 Montecarlo spec is for less oil but they ignored that and put in 2.5-ish litres. The "new" dipstick has a metal upper with an O ring seal whereas the previous one has a an all rubber upper. I'm confused on that amongst other things!

Leo

[A1.6HPE]

OK I'm up for tieing bits of string to the back of my car. Hope none of my friends see it though.

I have just replaced the transmission - the replacement one has a larger dipstick hole and the dipstick markings are higher up than the original unit. This ties in with my HPEW having the oil level much higher than the MAX mark. It seems as if the S2 Montecarlo spec is for less oil but they ignored that and put in 2.5-ish litres. The "new" dipstick has a metal upper with an O ring seal whereas the previous one has a an all rubber upper. I'm confused on that amongst other things!

Leo

[Allen Lofland]

Well, to call it a test is overstateing BUT Delmer Teets has this bad habbit of cleaning up with papper towels and one day he left some of them laying on the back shelf sort of close to the exhaust. At a good clip some time later he saw mucho smoko coming out of the TOP of the engine cover :)
this would correspond with the idea that air come IN at the tailight grill and OUT the top of the engine hatch :)
I asked Delmer if he would repeat the "TEST" while I followed his car with a camera and he said NO :( bummer, no cooperation at all. :)

[Will]

....that's basically what I did a few years ago Wallace- substitute "cassette tape" for "string" and you get the idea. Unfortunaltely, it doesn't really work like "if they are on the inside or outside" but more like, how MANY are on the inside vs.outside, and how many are stuck on the grill itself.
That's why I said I couldn't be sure without doing it again- I do have a video camera and that would probably help nail it down. I need to do a better test, clearly. I wish I had a smoker.
It SEEMED air was flowing outside to inside through the tail panel, based on the fact more streamers were inside, but I only used about 10 streamers- I should have had, like, 30 or so.
Maybe I'll go try again.
-Will