Stupid fuel tricks -or- Should I run E85?
#16
So here's what I just posted on my local 4x4 forum.
Most of you have have probably seen at least one of my threads regarding my stroker issues and I've got some info that you may find interesting. First off I''m 100% certain that the cam failure and valve spring failures had nothing to do with improper assembly or the fact I'm running a stroker, or that I'm cursed. Sometimes **** just happens. Okay? Alrighty then...
I'm a fookin' moron for running E85 in my heep! Yep I admit it. I read stuff on the WWW and believed that my rig was more than capable of running on E85 without further modification.
WRONG!!!!!
I got a call from the machine shop today and Robbie proceeded to tell me that all of my intake valves were useless because they were tulip-ed (like the flower). He also told me that they also should signs of getting very hot, so much so that the stems near the head were blue. He also told me that the cylinder head should signs of excessive heat as well.
Needless to say I has floored! I knew I was going to need a little machine work to replace a guide and a valve seat, but now I'm looking at at least 3 new seats and 6 new intake valves.
Here's a pic of the #1 combustion chamber. The yellow arrows point to the discolored area adjacent to the exhaust seat. The metal has yellowish color that turns to blue as you get closer to the valve seat itself. Hopefully the picture quality is good enough for you to see what I'm trying to describe.
Here's another chamber without the arrows added.
So what was the root cause? Insufficient fuel. Yep, that simple. In order to run E85 the Pulse Width must be increased to allow for more fuel to reach the cylinder. The extremely lean mixture burned so hot that the margin of the intake valves bent, giving it a concave shape.
So what now? 6 new intake valves, 3 new seats, removal of money from the bank to pay for it.
I know that some of you are wondering why the exhaust valves weren't affected and I asked the same question. Basically it's because the exhaust valve is smaller and the margin is larger than the intake valve. This should clarify it...
Just so there's no confusion, this is not a result of simple overheating. It's all about improper combustion as a result of poor fuel management. I've got no one to blame but myself for this one.
Flame suit is on, have at it folks.
I'm a fookin' moron for running E85 in my heep! Yep I admit it. I read stuff on the WWW and believed that my rig was more than capable of running on E85 without further modification.
WRONG!!!!!
I got a call from the machine shop today and Robbie proceeded to tell me that all of my intake valves were useless because they were tulip-ed (like the flower). He also told me that they also should signs of getting very hot, so much so that the stems near the head were blue. He also told me that the cylinder head should signs of excessive heat as well.
Needless to say I has floored! I knew I was going to need a little machine work to replace a guide and a valve seat, but now I'm looking at at least 3 new seats and 6 new intake valves.
Here's a pic of the #1 combustion chamber. The yellow arrows point to the discolored area adjacent to the exhaust seat. The metal has yellowish color that turns to blue as you get closer to the valve seat itself. Hopefully the picture quality is good enough for you to see what I'm trying to describe.
Here's another chamber without the arrows added.
So what was the root cause? Insufficient fuel. Yep, that simple. In order to run E85 the Pulse Width must be increased to allow for more fuel to reach the cylinder. The extremely lean mixture burned so hot that the margin of the intake valves bent, giving it a concave shape.
So what now? 6 new intake valves, 3 new seats, removal of money from the bank to pay for it.
I know that some of you are wondering why the exhaust valves weren't affected and I asked the same question. Basically it's because the exhaust valve is smaller and the margin is larger than the intake valve. This should clarify it...
Just so there's no confusion, this is not a result of simple overheating. It's all about improper combustion as a result of poor fuel management. I've got no one to blame but myself for this one.
Flame suit is on, have at it folks.
#17
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Year: 1999
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Ouch!
Sorry to read this. Very informative post, though. Thank you for sharing. Did you ever felt any signs of the engine running too hot?
It seems that we really need one of these conversion systems in order to run on straight E85
www.whitelightning.net
It seems that we really need one of these conversion systems in order to run on straight E85
www.whitelightning.net
#19
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Year: 1999
Model: Cherokee(XJ)
Engine: 4.0L
Wellp, the E85 project must be put on hold for now as I sold my '84 XJ. I am sure that running E85 in a carbed XJ would be possible with some minor mods.
#20
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Year: 1992, 2- 1998 (All 3, 4 Doors)
Model: Cherokee
Engine: 4.0L in all
Well E85 is not bad, like most people think. But I'm not gonna be the one to argue this. Here's some links:
Big Power on E85:
http://www.carcraft.com/featuredvehi...chevy_chevelle
http://www.carcraft.com/techarticles...chevy_chevelle
http://www.carcraft.com/featuredvehi...own_chevy_nova
Using E85:
http://www.carcraft.com/techarticles...e85/index.html
http://www.carcraft.com/techfaq/ccrp..._car_tech_tips
www.carcraft.com/techfaq/ccrp_0710_auto_repairs
Big Power on E85:
http://www.carcraft.com/featuredvehi...chevy_chevelle
http://www.carcraft.com/techarticles...chevy_chevelle
http://www.carcraft.com/featuredvehi...own_chevy_nova
Using E85:
http://www.carcraft.com/techarticles...e85/index.html
http://www.carcraft.com/techfaq/ccrp..._car_tech_tips
www.carcraft.com/techfaq/ccrp_0710_auto_repairs
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