2332 48IDA motor issues

[chateau la fete]

Hi

I have a mainly scat pro parts built 2332 motor
Wondering if anyone has any ideas or had the same issues before?!
Motor has around 4500 miles on it and suddenly started smoking in all rev ranges and popping (not quite a mis fire) in lower rev range.
I pulled all the plugs and the number 4 plug was covered in oil so I pulled the motor and took the head off (see picture). Number 4 on the head was covered in oil and number 3 was dry and sooty.
The heads are scat pro comp and trying to work out the likely cause of the oil getting into the cylinder, whether worn cylinder or rings, or valve guides??!!
Anyone had these issues with the scat pro comp heads?!

Thanks for any input

[Martin S.]

Pull the cylinder off and see if there's a broken oil ring/land. Nothing wears out with only 4500 miles so something must have broken for that much oil to get in there.

[chateau la fete]

Thanks , but all looks ok with the rings
I am going to measure the cylinder bore to see if in spec
There is very slight scoring on the top/back of the piston and in the cylinder, but not deep and feels smooth to the touch
Still not sure on the valve guides and if anyone has had any problems like this on the scat pro comp heads

[Jim Ratto]

How much oil did you run in the engine?

[chateau la fete]

I have a deep sump, external oil filter and external oil cooler
If I put in 5  litres the level will be halfway between minimum and maximum on a standard dipstick

[chateau la fete]

Engine is back together with new rings (cylinders were in tolerance), ran the engine back up and pretty much the same.
Checked oil again and there was too much in it, so I drained off the excess amount and it stank of fuel!!!!
Now thinking there could also be a carb problem, maybe jets, float bowl?!
I cleaned the jets not log ago and the car ran sweet with the jets that are in it.
Also using a lot of fuel and the car stinks of it!!

Anyone suffered this before

Thanks for any input

[Martin S.]

Don't drive it with gas in the oil, that will damage the engine. What fuel pump? The mechanical stock-style ones can leak, but look at your carbs before firing up the engine again and find the source of the gas. Gas in the oil happens on stock bugs when the choke heater element fails or the choke doesn't open up for some other reason. It could be a float or float valve stuck open, something simple like that. Careful not to ruin the bearings!

[chateau la fete]

Thanks

All of the jet sizes are the same from when it was running good and have been cleaned. I have a Holley electric fuel pump and regulator, none of which have been touched or adjusted.

I removed the tops of both carbs and both had roughly the same amount of fuel in and looks like no leaks as the bowls were holding the fuel.
Both float valves operate as they should. I have checked the floats for leaks and float height and they are good.

Valve guides??!!

[richie]

Holley regulators need constant monitoring, the pressure seems to change with outside temperature, 1st thing I would do is turn the fuel pump on and watch down the carbs for a minute or so to see if fuel is bleeding over[well after I had changed the oil], the fuel has to be getting in the oil somehow and leaking valve guides will NOT do this, if it smells that much off fuel its leaking somewhere and the only way it can get in the engine is to fill the intake so much it leaks past the rings if you don't have a mechanical pump
Did you hone the cylinders before you put the new rings in?
What carbs are they and what fuel pressure do you have? and what is a scat pro comp head? I only heads they sell I know of are the wedgeport, mini D, street port and the Scat Split ports heads

cheers Richie

[richie]

Just to clarify by what carbs I meant, what version, Italian/Spanish/American/Empi?

cheers Richie

[chateau la fete]

The heads are wedge port 44x 37.5
Carbs are italian webbers 48 IDA's

I will do a compression test

[DWL_Puavo]

Needle valves can be also checked by taking off IDA lid with needle valve and float, turning it upside down and then starting the (electric) gas pump. In my friend's IDA:s it was then easy to see where it leaked - the fibre gasket under needle valve was broken.

As the carb was leaking from overfilling the float bowl, excess gas leaked only into one throat. We found this out when the engine started idling with only three cylinders, it was still quite drivable. Thankfully we found this out quite quickly.

Here also, the bowls weren't leaking at all, we also stared them quite a bit without the fuel level dropping. It was only the excess gas leaking into other throat.

Puavo

[chateau la fete]

Thanks for that

I'll keep persevering with fuel checks on the IDA's

[chateau la fete]

Started to go through the fuel system. I have the following which has been on the car a few years and ran well:
Holley red fuel pump with in-line filter
Holley fuel pressure regulator 1-4 psi

I turned on the fuel pump and measured the amount of fuel coming out of the regulator going to each carb and more fuel was going to one carb than the other!!

Would it be good to put the CB performance rotary fuel pump with build in regulator and junk the holley stuff?
or go with a different regulator with a gauge? But which gauge and regulator would be best for my application?

[Muroc]

Also check that the floats in the 48 IDA  are not sinking (if there is a hole in them).
Otherwise your needle always stays open and fuel flows in the engine....

Don't forget to check your float level in the carb's tank.

[leec]

I really like the CB pump. World fine on my 2276cc with IDA's. I have had one fail on me so bought two new to keep one in the tool box

Lee

[chateau la fete]

Ok, now running a lot better!!

This is the conclusion, like many things it was a number of factors!!

I disconnected the fuel lines from the carbs and placed them in 2 clear bottles. I ran the fuel pump with fuel running through the pump and regulator into the bottles. I then measured the fuel in each bottle and 1 had twice the amount of fuel than the other.
I then disassembled the regulator and what looked to be some kind of built in filter, was blocked on one side hence the irregular fuel quantities - replaced fuel regulator.

Measured the float level in each carb and 1 carb was on the limit and the other was out of the the limit - re-adjusted.

Changed the oil, adjusted the syncing on the carbs and now runs a lot better.