Another reason for disliking the IDI

[Rot Box]

Its fairly often that I meet people who dislike the IDI's. Most don't like them because they never start in the winter, they have no power or they are just a big pos for reasons unknown (you guy's have heard it all before I'm sure ).

Anyway the other day my friend was taking to his buddy who is a well known high performance engine builder in my area. This guy also doesn't like the IDI's for a reason I've never heard of. Apparently the majority of the IDI's he's seen in his shop have seized the valves in the head and then they hit the pistons causing major damage I'm guessing it is due to excessive heat or not changing the engine oil often enough. What do you think? Ever heard of this?

Andrew

 

[FordGuy100]

Sounds like a rare occurance.

 

[hesutton]

Seems the 7.3's had more a tendency for bad valve guides than the 6.9. But, when the guides wear, the valve can move too much and get stuck against the seat. When that happens, the piston gives a death kiss to the valve and it's all over but the crying. If you ever hear a "chuffing/huffing" sound in the intake or exhaust......... pull the valve covers and have a look.

Heath

 

[icanfixall]

This valve sticking in the guides and kissing a piston started way back when these engines had an oil consuption issue. Turns out the vlave seals were the issue so... Like any good engineer would do they "invented" a positive sel on the vlave stems.... Wel guess what... Excessive wear on the valve stems and guides but sometimes the valves froze in the guides because of not enough oiling. So the great engineers developed yet another type of valve seal. This seal does not connect to the guides like most all other seals do. It snaps into the springretainer that locks the valve clips to the valve. This allows some oil to reach the guide but this is only on the exhaust valve... The intake has a positive seal and it gets plenty of oil from the cdr. So we all know its getting oiled. Evolution at its finest right there....

 

[Black dawg]

It has always seemed funny to me how certain car problems can be region specific.

IDIs are known for valve droppage and cavitation. I Have seen neither.

The only IDI failures I have seen are idit motors chucking rods.
Around here nobody hates ford idis and never have starting issues even though the glowplugs have been burnt out for 10 years. They either plug them in or use starting fluid.

 

[oregon96psd]

They either plug them in or use starting fluid.

isnt that a starting problem right there masked by an alternative way of getting them to start.....

 

[FordGuy100]

Yup but it gets the job done.

 

[Simp5782]

I dont have glow plugs, just ether injection. doesnt hurt it. She actually prefers it! If shes gonna go, let her go in pieces!

 

[Kevin 007]

This valve sticking in the guides and kissing a piston started way back when these engines had an oil consuption issue. Turns out the vlave seals were the issue so... Like any good engineer would do they "invented" a positive sel on the vlave stems.... Wel guess what... Excessive wear on the valve stems and guides but sometimes the valves froze in the guides because of not enough oiling. So the great engineers developed yet another type of valve seal. This seal does not connect to the guides like most all other seals do. It snaps into the springretainer that locks the valve clips to the valve. This allows some oil to reach the guide but this is only on the exhaust valve... The intake has a positive seal and it gets plenty of oil from the cdr. So we all know its getting oiled. Evolution at its finest right there....

What years did they change from a positive seal to the one that does not connect to the guides?
Im assuming its on the 7.3. What did oil consumption past the seals do to effect the valve/guide to start sticking? Just too much carbon buildup? I love the old 6.9 seals as I know the guides are getting oil when I watch the oil level on the dipstick slowly going down. I have seen WAY more 7.3's with ***** engines due to a dropped or stuck valve than 6.9's. And way more 7.3's with the CHUFF CHUFF noise than the 6.9.

 

[rhkcommander]

The intake has a positive seal and it gets plenty of oil from the cdr. So we all know its getting oiled. Evolution at its finest right there....

Sucks for the guys running road-draft tubes then eh?

 

[1994Diesel]

The guy sounds like he doesn't know what he is talking about. I have ran into people like that before....

 

[Kevin 007]

But the CDR vapor wouldn't lube the valves for the front 4 cylinders as all the vapor seems to get sucked into the rear 4.

 

[drewdole1]

over 400.000 miles on my 7.3

 

[Kevin 007]

Yup, just sold a 90 with 375,000 on it and ran like a top.

Whoever these people are that dislike or talk crap about our idi's likely are just not in touch with them, thus making it very frustrating to troubleshoot/work on them. All of use here know about the little pet peeves like air intrusion and where to look for leaks, we know to be careful removing glow plugs and which glow plugs to use and why the solid state controller stops working with two or more burnt out plugs, we know about cavitation and how to prevent it, we know we should use head studs when pushing big boost, and so on and so fourth....
These things are somewhat specific to idis more than they would be for most diesels, cummins included. So if someone who doesn't know them buys one, and it doesn't start in the morning due to air intrusion or whatever...it can be VERY frustrating to get it running right. I was in the same boat when I bought my first idi years ago. I knew diesels but there were many things for me to learn about idi's and im still learning. I thought they were junk to. Now im a new owner to a powerstroke, and im learning all over

But I must admit that that it would be hard for a guy who is used to a 12v cummins; to buy and like an idi because of course it will never start as well, it has glow plugs, less power, more air intrusion issues (IMHO). But now that I have learned the idi, I prefer it over the cummins because they have proven themselves and I like the underdog!! And I don't think its a POS anymore I like N/A engines because I have had better luck with them and I find the idi to be a fairly mellow, quiet engine that is content to putt around all day in all kinds of conditions. I don't have a heavy right foot anymore lol. Yet they will still tug a house if geared right

 

[MidnightBlade]

The only reason people hate my truck is because of the way it looks or because it will keep up with their fancy shmancy Cummins (and put on a better smoke show )