Faults in the IDI engine design?

[Andertusa]

That are the real design flaws or weaknesses that are inherent in the IDI engines?



P.S. - Sorry about this thread being similar to another thread I created earlier, the info gathered there there is helpful, but I would really like to know the flaws on these beasts, so where practicable, I can build a decent-lived Motorway MONSTER.

 

[Dieselcrawler]

Early 6.9 blocks cracking around block heater
Somewhat small head bolts on 6.9
Leaking head gaskets on rear of 6.9 engines
Crappy rocker design on 6.9
Crappy glow plug controller on 83-86 6.9
Cavitation on 7.3
Valve guides seem to be an issue on many engines
Dual mass flywheel on 5 speed trucks

Those seem to be the biggest issues in my mind

 

[BDCarrillo]

Fuel system has 60 something places it can leak or have air intrusion

 

[towcat]

there is no such thing as a "perfect" motor platform. All have attributes and shortcomings. you need to determine what you can live with and what will be the deal breaker. the only thing questions like the first post is ignite internet brawls.

 

[BDCarrillo]

I kind agree with towcat, but look at it as "what are the fixable issues, or things to keep an eye on" which oddly enough makes me think of the bullet proofing thread... It'll be a similar list

 

[Dieselcrawler]

Main reason I didn't list fuel issues. I tried to list the major issues guys including myself have had issues with.

 

[BDCarrillo]

I wouldn't call them flaws, weaknesses, or faults anyway... These are 21-30 year old engines; you are going to have aging and normal wear.

 

[IDIoit]

i really dislike the placement of the t-stat and the incoming water elbow. pain in the rear to get to.

i also dislike the valley pan and the intake gaskets being 1 in the same.

 

[madpogue]

I'm surprised that no one is making/marketing stand-alone intake gaskets.

 

[Waystro]

We get this question a lot
Best answer is READ READ!!
Most Fail but if you have Deep pockets anythings possible.

 

[IDIoit]

I'm surprised that no one is making/marketing stand-alone intake gaskets.

the intake can be done with straight RTV, thats how the PSD'ers do it.
i havnt had an issue at 22 psi.
its the valley pan that sucks.

when i get on my hotrod build, ill be making a .063" aluminum stand alone pan.
with no hole for the CDR or turbo return.

 

[dunk]

I've heard several mentions of block flex popping freeze plugs once you start getting into mild-moderate big block HP and torque levels. I assume screw in freeze plugs would solve this issue.

 

[Andertusa]

Thank you guys.