318is supercharged eaton m45 NEED HELP WITH PIPING ICV ETC

[TamTom]

I HAVE JUST FINISHED THE CONVERSION BUT CAN'T GET THE CAR TO START UP AND IDLE CORRECTLY.
The first time i started the car it idled and started but after a minute or so it started chucking oil out of the filler cap.
i realised the pressure was pushing through the rocker cover from the supercharger via the plastic pipe just after the air flow meter.
I will post pics asap!

appletree if you read this i think your're my man!! lol
your name seems to be popping up everywhere
thanks people

[TamTom]

Somebody please help!!!

[chu346]

Put a filter on the icv pipe and vent the pipe to the cam cover to atmosphere or a catch can.

[chu346]

Have you got a bypass valve for idle?

[TamTom]

is this a one way valve which connects from the plastic flexi pipe before the throttle body and connects the the idle control valve?
i have it connected up this way with the valve flowing towards the ICV but not back obviously.
Worked out that the factory piping was connecting the rocker breather pipe to the throttle body, when the car is idling with the supercharger it sends all the charge through the bottom pipe coming from the throttle body to the rocker cover which is charging the rocker case with air and blowing out oil from the filler cap!
Really baffled?
i have the BOV connected just before the throttle body circulating back to the inlet of the supercharger.
i was told to take the vaccum pipe off a t piece from the feul regulator, is this correct?

[GeoffBob]

is this a one way valve which connects from the plastic flexi pipe before the throttle body and connects the the idle control valve?
i have it connected up this way with the valve flowing towards the ICV but not back obviously.
Worked out that the factory piping was connecting the rocker breather pipe to the throttle body, when the car is idling with the supercharger it sends all the charge through the bottom pipe coming from the throttle body to the rocker cover which is charging the rocker case with air and blowing out oil from the filler cap!
Really baffled?
i have the BOV connected just before the throttle body circulating back to the inlet of the supercharger.
i was told to take the vaccum pipe off a t piece from the feul regulator, is this correct?

TamTom,

The Eaton M45 is what’s known as a roots pump. If not familiar with roots pumps I suggest that you read up on them. Lots of books out there and plenty on the net.

The basic problem you have here is that a Roots pump pumps a constant VOLUME of air per rotation of the pump shaft. Hence, at idle speed, your Eaton is trying to supply your engine with more air than it actually requires to idle. Since you have connected your ICV (if I understood your explanation correctly) to the rocker cover, it is logical that all you will do at idle is blow oil everywhere.

And, at a guess, I’d say the only reason you started blowing oil after about a minute is because that’s about how long it took for the one way valve in the hose to the rocker cover to fail under pressure. They really aren’t designed for that.

To counter the problem of making boost at idle, all superchargers must be fitted with a bypass valve, what you are calling your blow-off valve (BOV). However, by the sounds of things you have your BOV incorrectly plumbed in. The BOV diaphragm requires VACUUM from the engines inlet manifold (AFTER the throttle body) to literally SUCK on the BOV diaphragm and thus open the BOV so that the excess air from the pump outlet can be circulated back to the pump inlet. The fact that your BOV isn’t opening accounts for the fact that you are effectively making boost at idle, except that in your case you are pumping this excess air into your rocker cover!

First off, lose the hose from the throttle body/ICV to the valve cover. At least then she’ll stop blowing oil everywhere. Second off, get your BOV working properly. Check that it’s opening as it should by sucking on the line that goes to the BOV diaphragm.

Oh, and technically it’s a bypass valve on a Roots pump, not a BOV. BOV’s are really only required on turbochargers. The root of your problem is that you need a proper bypass valve to vent the excess air pumped by the pump each time you close the throttle down, such as when at idle.

HTH

Regards
Geoff

[TamTom]

Thanks for the help Geoff!
Tested the recirculating valve which opens under vaccum, where is the best place to buy one of these if i were to put a better one in its place?
Also is it important that the vaccum pipe for the bypass valve to be after the throttle body or after the butterfly?
I have a vaccum line running from the throttle body to the feul regulator this is where i have been told to pick up the bypass valve vaccum from is this correct?
Your help is much appreciated!!!
Tam.

[GeoffBob]

where is the best place to buy one of these if i were to put a better one in its place?.

I haven't a clue Tam, unless of course you're also down here in South Africa?

Also is it important that the vacuum pipe for the bypass valve to be after the throttle body or after the butterfly?

After the BUTTERFLY, extremely important!!! The point is, when the throttle (butterfly) closes down, the air pressure in the inlet manifold falls lower than atmospheric pressure (meaning a partial vacuum forms). Anywhere BEFORE the throttle body (butterfly) could still be at a positive pressure (boost) because of the supercharger. There is, therefore, a substantial pressure drop over the butterfly when it is almost closed. It’s this pressure drop that sucks on the BOV diaphragm (causing it to open) and the fuel pressure regulator (FPR).

I have a vacuum line running from the throttle body to the fuel regulator this is where i have been told to pick up the bypass valve vacuum from is this correct?

Should be fine so long as that line from the throttle body originates from AFTER the butterfly. If not then both your BOV’s diaphragm and FPR will be feeling pressure at idle and not vacuum!! I’d check that carefully if I were you. My line to my FPR comes from a connection that is tapped into the manifold so I KNOW that I have vacuum in that line. A connection to a throttle body can be deceiving since you are not sure if the source of that connection sits before or after the butterfly.

Get that sorted and I think you’ll come right for sure. And lose the breather from the rocker cover for the time being if you haven’t already.

Best of luck
Geoff

PS: And if you don’t yet have one, get a pressure gauge (one that reads both boost and vacuum) connected to your inlet manifold as well. That way you’ll know your intake pressure. I have no idea what your pulley ratio’s are, but you’ll want to know your intake manifold pressure lest you blow your engine up!

[TamTom]

CAN I RUN THE EATON M45 ON STANDARD INTERNALS OR WOULD I MELT IT?
I KNOW THE E30 318IS COMES WITH FORGED PISTONS AS STANDARDNOT SURE OF THE OTHER COMPONENTS?

IF I RUN IT ON STANDARD INTERNAL ECU ETC ETC WHAT IS THE WORST THAT CAN HAPPEN OR COULD I JUST TAKE IT EASY AND NOT FLOOR IT?

PLEASE GIVE ME YOUR OPPINIONS PEOPLE!!!!!!!

[GeoffBob]

Depends entirely upon what pulley ratio you have. The faster you spin your Eaton relative to your crank speed the more boost you will make and thus the greater the chance of damaging your engine.

Also depends upon whether you have an intercooler or not. All forms of forced induction heat the air that they pump - it's called adiabatic heating. Except that roots pumps are especially inefficient and do a worse job of it than any other form of forced induction pump. No pump needs an intercooler quite as badly as a roots pump does!

The reason I mention these two factors is because the phenomenon called "detonation" (when your fuel basically explodes rather than combusts) is driven by two parameters, namely the pressure and temperature of the air/fuel mix in the cylinder. And it really doesn't matter how strong the engine is, as prolonged detonation will eventually destroy any engine.

On stock internals with a CR of 10.1:1 on your M42 motor I would suggest that you choose your pulley ratios to keep your boost below 0.3-0.4 bar (4-6 psi). Should work fine on the high side if you have an intercooler, but definitely on the low side without one.

Others can tell you more about getting your Motronic ECU re-mapped. An effective countermeasure against detonation is to retard ignition timing. This can cost you torque (detune the engine) but does at least stop you from putting holes through pistons due to detonation. Of course, you'll need someone to look at reprogramming your ignition map for you to get this right. Assuming that you keep your boost low enough not to have to fiddle with your ignition timing you might get your fuelling right by using a rising rate fuel pressure regulator in order to enrich your mixture slightly while making low boost.

In all honesty though, if you want to do this properly (and get your moneys worth from your Eaton), you need to look at lowering your CR and having someone professionally tune your engine management with an AFR gauge fitted up the exhaust.

[GeoffBob]

TamTom, for additional info on fitting an Eaton M45 to the BMW M42 motor, please read this thread here

[TamTom]

tried to get the car running again using 1 way valves and switching pipes from and to various places all at no avail!
Tried connecting the idle control valve to the the inlet duct just before the throttle body so the pressure from the charged side would be flowing through to the ICV when at idle bypassing the butterfly and throttle body completely!
Also connected the pipe which comes from the throttle body before the butterfly to the rocker breather, which originally ran to the ICV.
tried many things using 1 way valves etc and trying different combinations etc!
Getting very disheartened!!!!!!!!!!
The pulley is around 10cm diameter on the charger and then run on 1 ribbed belt to all other ancillaries water pump, alternator etc which is turned by the crank!
Power steering is run on a seperate pulley!

Need to get through this rough patch,
Could i be running too much boost?

[GeoffBob]

You'll need to tell me the exact dimensions of your crank pulley and your Eaton pulley if I am to tell you if you are spinning your Eaton too fast (thus pumping too much air).


Tam, I think you may be confusing how some of these parts are intended to work, and you may not be aware of the fact that they won't work the same on a supercharged engine the way they do on a stock normally aspirated engine.

Any idle control valve functions to bypass the throttle body. That's its purpose in life. It allows a certain amount of air to escape around the throttle body (as opposed to passed the throttle butterfly) in order to control your engines idle speed. The fact that your engine is now supercharged means that your ICV absolutely MUST bypass air from BEFORE the butterfly to AFTER the butterfly. It cannot (MUST NOT) draw air in from any line that goes to the rocker cover or any other emissions control device on your engine - else you will blow oil everywhere! If you can't get it to work this way, then you have a problem.

Point of fact: If your bypass valve (your BOV) is not opening at idle your Eaton WILL try to supply too much air to your engine (its an air pump for goodness sakes, that's what it does - it pumps air). Hence, your engine will either idle fast or (if you have connected your rocker cover to somewhere between the Eaton and the intake valves) it will simply pressure your crankcase and rocker cover causing it to p!ss oil everywhere!

So, for the last time:

1) Disconnect your rocker cover breather hose from your system. Leave it hanging for the time being. Your Eaton must in no way be able to pressurise your rocker cover or crank case. Are we clear on this?

2) Block off any outlets on the line between the Eaton and your inlet manifold that may now leak air. We don't want your Eaton leaking air anywhere, except for when your bypass valve (BOV) opens.

3) If you are going to use an ICV then for goodness sake, it needs to work so as to bypass air passed the throttle body butterfly. That's it's job in life.

4) If your engine now idles high (because your Eaton is trying to pump too much air into it, which it probably will do) then get your bypass valve working properly. So long as your bypass valve is open it will prevent the line from your Eaton to your throttle body from becoming pressurised, thus allowing your engine to idle normally.

If all of the above fails then check the operation of the throttle butterfly and the idle control valve. If the throttle or ICV are open too wide then it's no wonder you are pressuring your inlet manifold (keeping your bypass valve closed) causing your engine to make boost and rev high no doubt.

As a last resort, unbolt/remove your bypass valve (BOV) so that your Eaton can't build ANY pressure whatsoever. Your engine will now be normally aspirated once again. Get her idling properly while running normally aspirated, and then you can look at reconnecting your BOV. Once the BOV is back on, if the fast idle returns then, clearly, your BOV isn't working as it should. Probably because either:

a) You don't have the BOV diaphram connected to the correct place (should operate under vacuum from the manifold, AFTER the butterfly), or

b) Your butterfly/ICV are just too damn wide open to allow a vacuum to form in the manifold in the first place. Without the required vacuum (suction) from the manifold the BOV will simply remain closed. In which case, remove the ICV (blanking off the holes left behind) and adjust your butterfly manually until she idles properly.

[TamTom]

will i run too much boost if i use the e36 crank pulley directly running the standard eaton 45 pulley which is about 7cm i think ?

[GeoffBob]

Have you tried what I suggested above? If so, please give feedback. Very difficult for me to suggest a solution if you don't provide feedback on the status of your problem.

will i run too much boost if i use the e36 crank pulley directly running the standard eaton 45 pulley which is about 7cm i think ?

The stock Eaton M45 pulley is 2.5 inches diameter (63.5mm), and your crank pulley is 140mm diameter (I think ???).

Your Eaton M45 pumps 750cc of air for each rotation of its pulley. Your M42 motor, on the other hand, inducts 900cc of air for each rotation of its crank. Hence, with your pulley ratio of 2.2:1, your Eaton will effectively pump 2.2 x 750cc = 1650cc of air per rotation of the crank.

However, since your M42 engine only inducts 900cc of air per rotation of the crank, the added air inducted by the Eaton must be accounted for as a rise in pressure at the Eaton’s outlet. The pressure ratio (measure between the Eaton inlet and outlet) is thus equal to 1650cc/900cc = 1.83. The pressure within the inlet manifold is thus raised to 1.83 times atmospheric pressure. If you live at sea level then your atmospheric pressure will be roughly 14.7 psi (1 bar), and thus your intake pressure will be 27.0 psi (absolute). Your boost pressure will thus be 12.3 psi (0.85 bar).

Due, however, to the poor air seal around the Eaton’s compressor blades at low engine speeds, you will only see this boost from around 1500rpm upwards. However, even at idle, your Eaton will be attempting to supply too much air to your engine, which is all the more reason why you must get your bypass valve working properly.

Take note that it is not advisable to boost your stock 10.1:1 compression ratio M42 motor to 0.85 bar due to the extreme likelihood of detonation and pre-ignition. My suggestion is that you look at fitting a decompression (extra-thick) head gasket in order to lower your engines compression ratio.

Unless you set up your pulley sizes so that your Eaton only supplies the exact amount of air required by your engine (in which case it will make no boost at all, EVER) then you will have to accept the fact that you must re-circulate back to your intake the excess air produced by your Eaton at idle. And to do so requires a properly functioning bypass valve.

Alternatively, in desperation, you could relocate your throttle-body to BEFORE your supercharger’s air intake. This is the common way of plumbing in an Eaton and avoiding the problems that you have experienced.

[TamTom]

Thanks Geoff,
will a megasquirt system help to run more boost or will i still need to lower the compression?
I have already installed larger injectors 250cc i think!
I have checked the functioning of the recirc valve and it is opening as it should but i have been advised to release to atmosphere instead of recirculating!
I will try this tomorrow hopefully this will cure the idle problems, i dont think the recirc valve is recirculating the boost quick enough which causes the air pressure at the butterfly.
I'll post some ics and a video after tomorrow to give a better explanaition!
Sorry geoff i know it is all a bit confusing without seeing the problem.
Thanks for the support so far,
Tam

[GeoffBob]

will a megasquirt system help to run more boost or will i still need to lower the compression?

Any kind of aftermarket engine management (Megasquirt or otherwise) is recommended if you plan on running 0.85 bar of boost. Alternatively, you at least need your existing management re-mapped. Ideally you would want someone to re-map the fuel and ignition maps for you on a dynomometer. And at 0.85 bar of boost you'll definitely need to lower your compression ratio. Short of fitting lower compression pistons you'll at least need to look into fitting a thicker head gasket, else detonation will come knocking! Also, keep in mind that while retarding your ignition timing (making the spark occur later in time than you would like) will help you to avoid detonation, it does so at the expence of torque. Retarded timing is little else other than a bandaid for a problem that you shouldn't have in the first place.

I have already installed larger injectors 250cc i think!

At 0.85 bar boost on an 1800cc M42 motor you are looking at around 240hp total engine power output. At an AFR of 12:1 that equates to at least 1220cc per minute of fuel. Since the M42 is a four cylinder engine, that equates to four 300cc/minute injectors running at 100% duty cycle. Since you don't want to exceed an injector duty cycle of 85%, I'd recommend you at least fit 350cc/minute injectors. 250cc/minute will not be sufficient (this assumes that you will in fact be running 0.85 bar of boost). Also, don't expect to see that 240hp I mentioned at the flywheel. You can expect to spend at least a good 25hp driving your supercharger. This also assumes that you can run the engine to this sort of power level without encountering detonation, and without an intercooler and lower compression ratio, I doubt that you will.

I have checked the functioning of the recirc valve and it is opening as it should but i have been advised to release to atmosphere instead of recirculating!

It really doesn't matter which you choose to do, so long as the air that you release doesn't by-pass your air flow meter (AFM)!! You do not want to go releasing air that has already been "counted" by your AFM. It's the job of your AFM to tell your engine management that you are inducting X-amount of air so that it can add Y-amount of fuel. If you are blowing off some of that air then your engine will run rich. If I understand your system correctly thus far, then your AFM sits before your Eaton, right? That means you must recirculate air from the outlet to the inlet of the Eaton. Don't blow it off to the atmosphere and don't blow it off back into the your AFM.

i dont think the recirc valve is recirculating the boost quick enough which causes the air pressure at the butterfly.

Tam, if you have pressure creeping passed the butterfly into your inlet manifold, then your valve won't even be opening!! It needs vacuum to open, which only occurs when the butterfly is closed and pressure from the supercharger can't get passed. Then, provided the recirculating valve is large enough (a good 25mm bore diameter will be more than sufficient) your Eaton will vent quite easily the pressure that it would otherwise build up and ultimately blow open your butterly valve. Keep in mind that systems where the throttle sits AFTER the Eaton are very tricky to get working. If the Eaton has nowhere to vent its pressure it will quite literally blow open the throttle butterfly. So many people have encountered this problem that the easy solution is to move the throttle to BEFORE the Eaton, not after it. This is a guaranteed cure for your problem, although there is no law that says you can't make your current system (as it stands) work properly.

Just to be certain, can you please check that the diameter of your crank pulley (the one driving the belt that goes to the Eaton) is in fact 140mm. I have this figure in mind as that's what Appletree and Rix313 have on their cars, but you had better check before I offer you worthless and incorrect advice. FYI, if your crank pulley is in fact smaller than the 140mm I have in mind, then your boost will be less.

[TamTom]

Thanks for the help matey!
Getting there slowly but shurely!
It's good to know people are out there to help out of goodness.
Thanks again Geoff

[TamTom]

does anyone have a piping diagram they used for their install showing where the icv takes from and how the bov recirulates the air. also where does the afm sit in relation to the other pipes!
Thanks, Tam
info@tam-tom.com

[TamTom]

does anyone know if the eaton m45 has any more than 2 pipes? 1 inlet and 1 outlet?
I have seen in other diagrams and picture where it looks like there is a recirculating pipe inlet and dont want to strip it all out again to check.

[TamTom]

[img]http://s1080.photobucket.com/albums/j33 ... oto2-1.jpg
[/img]http://s1080.photobucket.com/albums/j33 ... o-1.jpg%26
[img]http://s1080.photobucket.com/albums/j33 ... 3-1.jpg%26
[/img]http://s1080.photobucket.com/albums/j33 ... 4-1.jpg%26
[img]http://s1080.photobucket.com/albums/j33 ... 5-1.jpg%26
[/img]http://s1080.photobucket.com/albums/j33 ... to8.jpg%26

does anyone know what the pipe with the bolt in is for on the supercharger?

Also any advice on relocating components and piping like the swirl pot and feul lines etc.

[GeoffBob]

Would help immensely if the pics were visible.

[TamTom]

that was my aim geoff, lol,
i am new to posting and have to work out how to post pictures.
Not quite sussed it yet.

[m_jermyn]

all the info needed is here

http://www.e30zone.net/modules.php?name ... c&t=171644

[TamTom]

Anyone know what the blanked off hole is used for on the eaton 45 supercharger?
This is just covered by a bolt!

[/img]



[/img]

[/img]

[TamTom]

[img][img]http://i1080.photobucket.com/albums/j33 ... oto3-1.jpg[/img]

anyone know the co readings i should be aiming for too?

I am getting 9.06 co and HC 462ppm

got a second reading of 6.76 and 385 after fiddling with the afm!
not sure what does what on the afm.

there is the circular spindle and the small blue screw on the side?[/img]

[appletree]

The bolt in the red hole is normaly for the brake servo iirc, that's what I used it for anyway, real oem might give you a drawing go it I'd you have a look.

In you application though it can just be blanked off properly with a bung

[smith4130]

sorry.... wrong place for my question...!

[appletree]

The blanked off hole with the red push fit goes to the bypass valve on the mini but they run the throttle before the charger un like your set up.

[appletree]

The blanked off hole with the red push fit goes to the bypass valve on the mini but they run the throttle before the charger un like your set up.