2007 5.9

What are the possible side effect of running too much cetane??

I've come to the conclusion with the help of a good friend of mine that I might have too much cetane in my tank and causing detonation at high rpm and high cyl pressures...any thoughts?

It detonates with and without Smarty and MP-8 hooked up.

Sounds similar to Tritons rattle down low but mine is above 35psi and 50% throttle.

cquestad

How did you get too much cetane?

enafzige

^^^^ Likewise, how do you have too much cetane? Did you extremely overdose an additive?

Cetane is a measure of ignition delay between start of injection and start of combustion. A higher cetane number means the fuel will burn quicker when its injected; thus, a fuel with a high cetane has the effect of increasing timing.

Normal cetane should be around 42 - 55. Anything higher than 55 gives no benefit. The upper cetane fuels are usually reserved for higher rpm diesels because more complete combustion can be had with the shorter burn times.

If you accidently overdosed on the cetane for a tank, just retard your timing a little and you should be fine...

--Eric

2007 5.9

I think I got too much cetane from putting in 3-4 times the amount of PS in last week and running a B20 mix on top of it.

My thought was that the stupid amount of PS combined with the Bio (that contains Methanol), has made for a perfect environment for pre-ignition.

Are my thoughts wrong, little guidence is needed.

My rattle ONLY happens with increased fueling and above 35psi and 50%+ throttle.

Running on STOCK tune still does it but only very faintly.

RowJ

I can tell you the PS additive WILL NOT mix with the BIO fuel! With only B20.... probably will mix ok with the 80% diesel fuel.
I don't think Cetane is your problem. It takes a min of 40 Cetane rating to start a diesel. Most fuel sold at the pump is 42 Cetane.
In some agricultural states, Premium Diesel fuel is sold w/ Cetane rating of 50 min. It would take more than you added to get your Cetane up to 50... let alone higher. A recommended dose of PS only raises Cetane 2 points.
You just have an overload of the Heavy Aromatic Napha used as a carrier in the PS product.
It is a solvent, and a methanol derivative, I believe, so alcohol is your problem.

Not a serious problem, IMO.
Easy driving at low power setting and topping off with #2 often (to thin the mix) should solve your detonation problem....
without hurting anything.

RJ

RowJ

Better yet.... drain 1/2 out with FASS or AD water separator (or whatever you have) and fill with #2.
I had to do this when out of town and had an acci-don't (negative accident). Found a GAS pump, on way to Florida, with a green handle!

RJ

2007 5.9

I am just going to drive it with no tunning in it until the tank is empty. I need to remember what its like to drive a laggy pig once in a while.

Thanks for the help.

2007 5.9

Found out that my rattle wanst from too much cetane...found 2 missing nuts on the turbo to manifold flange. So under higher boost when the DP gets up there, it was pushing the turbo away from the manifold and big exhaust leak.

sid325

Serious? Did the nuts just work themselves loose or did the bolts break? Glad you found the source. I thought we were gonna have to medicate you...

Jacob