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Is this a valve problem :(

Posted: 19 Mar 2013, 21:08
by BOXY
Decided to fit a new rocker cover gasket this evening and noticed one of the tappet adjusting screws looked wrong? I spun the engine over by hand to get the both the valves closed at TDC on No3. I backed off the nuts and adjusters and then wound them it until they were just touching. The inlet screw is touching a good few turns before the exhaust one does, and the valve spring even looks like it's higher. I guess this is a symptom of either a stretching valve stem or a recessing valve seat?

Image

So is it time for a new head or do you think I might be lucky and just need a new inlet valve? Educated, crystal ball assisted answers welcomed :)

Re: Is this a valve problem :(

Posted: 19 Mar 2013, 21:39
by kevtherev
Is there a problem with the engine and it running?

Re: Is this a valve problem :(

Posted: 19 Mar 2013, 21:43
by Oldiebut goodie
Presumably there are collets on the valve stem? Are they mis-placed or one missing on one?

Re: Is this a valve problem :(

Posted: 19 Mar 2013, 21:44
by kevtherev
It might be a lifter problem

Re: Is this a valve problem :(

Posted: 19 Mar 2013, 22:29
by BOXY
Is there a problem with the engine and it running?

The engine seems to be down on power again, but there aren't any rattles or smoke trails. On a run across Dartmoor a week ago I seemed to be having to go into first gear pretty early on some of the steeper climbs.
The van was being a bit wheezy last August and I set the tappets up with a .006" gap because it's a recon engine with solid lifters (possibly). That seemed to give it a bit of a boost in performance but obviously wasn't a permanent fix. If I get home from work early enough tomorrow I'll re-gap all the valves and see if that helps to regain a few horsepower.

Presumably there are collets on the valve stem? Are they mis-placed or one missing on one?

Yep collets are in place and there's no lateral movement in the spring. One of the inlet valves on the other side sheared at the collet last year, maybe this one is planning a similar break for freedom?

Re: Is this a valve problem :(

Posted: 21 Mar 2013, 18:21
by sarran1955
Hello,

For what its worth... :)

Check that the pushrod is free to turn when the cylinder is at TDC,

I have had, particularly with certain types of hydraulic lifter, cases where the push rod has 'jumped' out of the centre dish, and managed to lodge itself on the outer rim,.. :shock:

Causing wrong valve timing, even loss of compression....

Do your valve timing with the plugs out , set once then turn the engine over 3 times, 'feeling' for any lumps...

and then re set the valves.... yes.. again...

Why.... because as the cam shaft lobes wear, the sweet point fades, and gets wider... so less precise to tune.. :wink:

Hope this helps,

Cordialement,

:ok

Re: Is this a valve problem :(

Posted: 22 Mar 2013, 18:31
by Jokerbetty
Hi All. This sounds so much like the problem I am having and makes very interesting reading. Last October I had new hydraulic lifters fitted to one side (1.9 dg)that had got VERY noisy and were causing huge loss of power, and have thought since that it was slightly down on power. Garage said theyt did 2.5 turns after contact. This January I have done the other side and set the rockers myself (1.5 turns after contact) after this side got VERY noisy and was losing power.

I wonder if I can return Betty to her original power??

How much diference does setting the lifters make? Coiuld I notice a big difference if
1- The 2.5 turns is too much and opening too early?
2 - I set the lifters slightly off TDC for each piston (as this was my first time and was not sure what I was doing)?

She flew around france last summer but now even though she runs really well and starts well and no more rattles, she doesn't seem to pick up like before, or have power through the rev range.

Also, can I simply adjust the timing without a stobe to see if that improves performance. and how do I do it?

Also if nothing will bring back the power, are there effective tuning ideas to increase BHP a little??

Finally - I know I am rambling but it is friday and the first cork is popped :-)

Any help appreciated

Re: Is this a valve problem :(

Posted: 22 Mar 2013, 18:41
by kevtherev
Jokerbetty wrote:Hi All. This sounds so much like the problem I am having and makes very interesting reading. Last October I had new hydraulic lifters fitted to one side (1.9 dg)that had got VERY noisy and were causing huge loss of power, and have thought since that it was slightly down on power. Garage said theyt did 2.5 turns after contact. This January I have done the other side and set the rockers myself (1.5 turns after contact) after this side got VERY noisy and was losing power.

I wonder if I can return Betty to her original power??

How much diference does setting the lifters make? Coiuld I notice a big difference if
1- The 2.5 turns is too much and opening too early?
2 - I set the lifters slightly off TDC for each piston (as this was my first time and was not sure what I was doing)?

She flew around france last summer but now even though she runs really well and starts well and no more rattles, she doesn't seem to pick up like before, or have power through the rev range.

Also, can I simply adjust the timing without a stobe to see if that improves performance. and how do I do it?

Also if nothing will bring back the power, are there effective tuning ideas to increase BHP a little??

Finally - I know I am rambling but it is friday and the first cork is popped :-)

Any help appreciated

re lifters
read this and follow the instructions to the letter

http://www.ratwell.com/technical/HydraulicLifters.html" onclick="window.open(this.href);return false;

the only way to increase bhp to have any effect is change the engine for DJ2.1 or a car engine

Re: Is this a valve problem :(

Posted: 22 Mar 2013, 20:15
by Jokerbetty
Cheers Kev. That is a very detailed explanation - Ta Much. I am away this weekend but will buy a compression guage and try to set them precisly. Thats great and really encouraging as it sounds like the rough adjustment might be to blame.

I will try to set in the evening next week and let you mnow if there is an improvement,

:ok

Re: Is this a valve problem :(

Posted: 27 Mar 2013, 21:02
by Jokerbetty
Hi again

I set the lifters last night took it for a spin and it was definitly back up to full power - excellent :-) but a little ticky :-(

Took it to work this morning and it still has the power but the lifters seem to have picked up the slack and the ticking noise is gone :-)

Thanks for the advice and I will take it away to camper fest in chester this weekend then on to abergevenny next week - happy days

(I will make sure the heater is working though. :D

Re: Is this a valve problem :(

Posted: 27 Mar 2013, 22:14
by kevtherev
:ok

thanks for the happy conclusion

Re: Is this a valve problem :(

Posted: 04 May 2013, 17:18
by BOXY
I've got to the bottom of my van's lack of power.

Image

This picture was looking down the inlet port at the remains of the valve seat. I had a replacement head fitted this week and normal service has been resumed.

Re: Is this a valve problem :(

Posted: 04 May 2013, 17:47
by kevtherev
good grief :shock:

Re: Is this a valve problem :(

Posted: 04 May 2013, 17:59
by BOXY
The amazing thing is the van was quite happy on a 30 mile trip to the garage, pulling 60-65 mph on the flat. I've got the old head in the back of the van at the mo'. It was an ANC replacement fitted, I guess, when the Vege recon was done about 30k miles ago. I'm going to pop the valve out next week to see how bad the seat is. At least I've got a nice big VW paper-weight.

The garage confirmed that my van does have solid lifters while they had the head off. This afternoon when I was refitting the tin-ware seal I noticed the remains of a sticker that probably used to have the gap for the lifters on it.

Image

Re: Is this a valve problem :(

Posted: 06 May 2013, 19:38
by Hendrixevo147
Jokerbetty wrote:Hi again

I set the lifters last night took it for a spin and it was definitly back up to full power - excellent :-) but a little ticky :-(

Took it to work this morning and it still has the power but the lifters seem to have picked up the slack and the ticking noise is gone :-)

Thanks for the advice and I will take it away to camper fest in chester this weekend then on to abergevenny next week - happy days

(I will make sure the heater is working though. :D

JokerBetty,
Any chance of popping round to do mine before we all go to Shell Island ?
Evo