2.5NA down on power

Yes, I know, with a 2.5 NA how can you tell...very funny...

My daily driver 110 - 2.5 NA has been acting odd. While driving along at a steady speed the engine feels like it's missing beats - a bit of a stutter that was not there previously. Not hugely smoky, though i am noticing a bit of blue smoke that may or may not have been there previously.

Injectors were serviced 10K miles ago or so, no obvious leaks, fuel filter in the last 2K miles.

Wondering of maybe I've got an injector that's gone off or got clogged - and if so how to find it without yanking them all (don't have 4 sets of washers in the shop or I'd have done it already - I have a Merlin pressure tester)

Talk to me, guys...need some advice on this.

On a good note, though, it gave me a reason to drive my 109 to work today. Love that truck, but the cart springs and my back don;t get along as well anymore...

ajr

What does a compression tester tell you?
Are you burning oil?
Is your injector pump delivering the same amount to each pot?
What is the condition of your timing belt?

OK, specifics after some investigation:

Compression is constant across all 4 and commensurate with an engine with 200K.

No idea on the pump, though cracking off each pipe at idle results in about the same drop.

Filter service did nowt - they weren't bad and no bio problems in the oil in the tank.

I would hope I'm burning oil - it's a Diesel. . No, I am not burning oil Consumption is the same as it's been for the few years I've owned it.

Timing belt has 10K on it.

I'm pretty convinced it's an injector - I get a stumble/miss under load that is not there at idle except for a minute or two after start up. What I suspect has happened is i've got an injector that's partially clogged or gone off calibration, so it's not timing right off idle. Got new crush washers coming in from my supplier and I'm going to yank the injectors and check them for pop and pattern this weekend (ah, the joy of owning a Merlin injector tester). Until then I can live with it - it's not impossible to drive though not quite as clean as I'd like to see it.

ajr

If it's an injector you'll likely be able to see a difference just by looking at it straight away. Fingers crossed.

zeaphod said:

If it's an injector you'll likely be able to see a difference just by looking at it straight away. Fingers crossed.

Click to expand...

Just to conclude this thread for the search engines it turned into an absolutely annoying goat rodeo. 4 S***part injectors (recalibrated) in, then out because of horrid smoke levels, then 4 recons from Allmakes in...and the truck is transformed.

Power is back up nicely, smoke is minimized, and the old bugger runs like a charm. The pintles were just plain worn out on the original CAV injectors in the truck and had I been able to get pintles easily (long story with a supplier on vacation) I would have just rebuilt the ones I had, but the rebuilt injectors turned out to be the easiest course in the end. I'll eventually rebuild the CAV ones just to have them, but hopefulllly I won;t have to touch them again for a long time.

ajr

mrchurchill109 said:

Just to conclude this thread for the search engines it turned into an absolutely annoying goat rodeo. 4 S***part injectors (recalibrated) in, then out because of horrid smoke levels, then 4 recons from Allmakes in...and the truck is transformed.

Power is back up nicely, smoke is minimized, and the old bugger runs like a charm. The pintles were just plain worn out on the original CAV injectors in the truck and had I been able to get pintles easily (long story with a supplier on vacation) I would have just rebuilt the ones I had, but the rebuilt injectors turned out to be the easiest course in the end. I'll eventually rebuild the CAV ones just to have them, but hopefulllly I won;t have to touch them again for a long time.

ajr

Click to expand...

Glad you pinpointed it and got it sorted

I am not surprised to hear that, it was suggested by the manufacturer that that sort of injector was checked, and rebuilt if necessary, every 40,000 miles. Sadly not many operators now bother to do this, which leads to the sort of problem you describe.

mrchurchill109 said:

Just to conclude this thread for the search engines it turned into an absolutely annoying goat rodeo. 4 S***part injectors (recalibrated) in, then out because of horrid smoke levels, then 4 recons from Allmakes in...and the truck is transformed.

Power is back up nicely, smoke is minimized, and the old bugger runs like a charm. The pintles were just plain worn out on the original CAV injectors in the truck and had I been able to get pintles easily (long story with a supplier on vacation) I would have just rebuilt the ones I had, but the rebuilt injectors turned out to be the easiest course in the end. I'll eventually rebuild the CAV ones just to have them, but hopefulllly I won;t have to touch them again for a long time.

ajr

Click to expand...

Thanks for the summation.

Cool handy tip for any of us finding ourselves in the same boat

Ed