Club 80-90 Forums

Hi Guys,

I have a T25 1.9 dg 1983, it's been running well but noticed the tappets seemed noisy so decided to adjust them at the weekend. 

As usual nothing on these vans is as straight forward as planned, got to the last set and noticed some movement on the rocker. So I had been loosening off the 15mm nut, turning the adjuster with a screwdriver until it just made contact with the push rod and then adjusting 2 full turns and then locking off. 

However the last one on the passenger side, closest to rear bumper is not held shut, so when you press the rocker to check it's tight before adjusting 2 turns, it can move freely so you can't tell how much to adjust it. If you rotate the engine, it will move open when it should but it just doesn't have any pressure holding it the rest of the time. It's a little hard to explain so I've shown a link of a video on google to hopefully show it better.

I'm wondering if a hydraulic tappet is no longer holding pressure and that's why I can push the rocker back down when the valve is shut?
Any ideas would be appreciated thank you

https://photos.app.goo.gl/tFwxnMSr4JNpTHEM8

There's a video of the engine running aswell, they never seem to sound smooth on a video but don't know if mine is good/bad. The smoke is just a small bit of oil that leaked when I took the rocker cover off
 

That says either you hadn’t run the engine up to temp and the tappet wasn’t full of oil and up to pressure or it’s loosing pressure and needs replacing . 
two turns is too much for a previously used tappet that is up to pressure iirc . 

I used to have a similar problem on mine, whereby a tappet would be sounding louder than others until the engine warmed up, I found that an oil change remedied the problem, as there may have been a bit of gunk stuck there or maybe I was just lucky with the oil change.

Yeah I did have a read of the Haynes manual and a few threads online and most seemed to say 2 turns which is why I went for that. I hadn't run the engine up to temp as didn't see that that in any instructions but the van hadn't been left standing for long. It's weird as all the other ones were fine.

It looks like I'd have to remove the pushrod tube to get access to the tappet, this can be done with the telescopic type new style tube?

I spose I could run the engine up to temp and try again to see if it made any difference?

If your van has been sitting for a while it will be tappity. To check the lifter you'd have to take off the rocker assembly off to remove the push rod even if you have the telescopic tubes. You can remove the pushrod tube and gain access to the lifter then, to take it out you can use a magnet, might be a bit messy with oil coming out of the engine if you aren't on the level.

Might be best to run the engine til it's up to temp then try adjusting. If it's still the same you might need to replace a lifter, it could be you have a clip on a lifter that's gone awol and its not doing it job. While you're at it check your pushrods by rolling them on a flat surface. If they are bent they wont roll and it would be best to replace the bent ones for sure.

I think it is recognised that two turns from touch is for a new unused lifter, but too much for a used one. 

I would re adjust after running the engine for a good while , sometimes it can take a few miles to bleed them all up , depending on how long it’s been stood, and how leaky they are . 
once they are bled up then adjustment will be accurate . It not uncommon to just have one that bleeds down and the rest are ok 

Yeah it hasn't been stood, I've been using it at least every two days to go to work for the last few weeks a s that's 8.5 miles each way.

Any idea what the turns should be on used ones then, maybe 1.5 turns?

OK it sounds like I could remove the tappet by taking off the rocker to gain access to the tube and then rescuing it with a magnet on a stick type tool? Hopefully not having to remove the head!

You dont need to remove the head, just the rocker arms assembly and the pushrod.
and 1 and a half turns should do it for the adjustments.

Ok thanks, I'll run it up and recheck just in case it had drained, if no luck then I'll get a new tappet.

what's the advantage of telescopic push rod tubes if you can remove them normally without taking the head off then?

Ads1987 wrote:Ok thanks, I'll run it up and recheck just in case it had drained, if no luck then I'll get a new tappet.

what's the advantage of telescopic push rod tubes if you can remove them normally without taking the head off then?

Because you destroy the tube when removing it. You'll need to compress the telescopic one to fit it, and it expands to seal at both ends.
But first try something like Wynn's hydraulic tappet cleaner oil additive. I've had some success over the years with it. Or just change the oil, get it warm for at least 30 mins or a >5 mile fastish run, and adjust to 1.5 turns. It's only new KS tappets that like 2 turns IME.

Sent from my ONEPLUS A3003 using Tapatalk

Ok thanks, will give that a go First, was thinking about the lifter additive so I'll go for that too