Tappets and cams

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ermie571
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Tappets and cams

Post by ermie571 »

Hi folks,

we are talking 2lt a/c recon engine with manual tappets.


was reading T Wilson's rebuilding your air cooled enjine last night (interesting bed time reading), and it says that hydrualic lifters (is this another name for tappets??) need a different cam shaft and followers (i think) to mechanical lifters. :?

so....does this mean that I can't replace the heads to get cylinder 2 to work??? :twisted:

Would a recon place really put a new cam shaft in when changing to mechanical lifters?? Was going to replace the heads but won't if it will burger the enjine.

Any ideas?

Emma
2.1 DJ 1990 Caravelle (died and gone to heaven)
2.0 AGG (1997 ish) 1984 transporter LPG

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toomanytoys
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Post by toomanytoys »

heads are nothing to do with lifter cam wear...
Cam and lifter "should" be matched.. and if they fitted new lifters then they hopefully used the correct cam..
Hydraulic lifters need a different cam profile..

if you need a new head then fit it..

If you have "solid" lifters then you have to do the valve clearances every so often..

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Post by ermie571 »

TooManytoys,

thanks for the info.

Will fit the replacement heads to see if there is any improvement in cylinder 2. Fingers crossed!

Emma
2.1 DJ 1990 Caravelle (died and gone to heaven)
2.0 AGG (1997 ish) 1984 transporter LPG

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toomanytoys
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Post by toomanytoys »

But what has been determined as the problem for no2???
Burnt/loose valve seat?

Or is it just that someone has made the valve clearances too tight?

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ermie571
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Post by ermie571 »

Hi Toomanytoys,

perhaps you didn't see my posting in chat the other week

https://club8090.co.uk/forum/viewtopic.p ... highlight=

Its been a bad day.... in chat.

Would welcome your opinion, if you would like a read.

Emma
2.1 DJ 1990 Caravelle (died and gone to heaven)
2.0 AGG (1997 ish) 1984 transporter LPG

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toomanytoys
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Post by toomanytoys »

what are the valve clearances now??
If its dropped a valve seat then you could swap the heads for some with expertly fitted seats..

Type4 heads are bad for dropping seats, its completely possible that they used a set of head that "looked" good.. in any type4 head it is totally required to change the seats as vw screwed up on the interfeance fit ofthe seat in the head.. this is ok, until the engine is over heated a bit..

So the other thing is... Is all the tinware in place and in good order? engine bay seal etc.. Timing correct (this will kill an engine sooner than anything) and everything else in good working order...

If the bottom end is leak free and good oil pressure, then heads would do.. but it depends on the price of the heads and fitting etc.... you might be near the 900 of the elite engine...

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Post by ermie571 »

Hi toomany toys,

well, the valve clearances are the 8 thou marked on the rocker covers. Pete showed us how to set them. Yes, they were tight....but loosening them made no difference to the engine. :twisted:

Spannerack has a set of heads that he believes to be good, and doesn't want the earth for them. I was going to try and just replace the head to see if that recitified anything. We have someone on hand who is happy to give advice and guidance. If it doesn't then.....who knows....

Tin ware all present and correct. Oil in engine, with no leaks. Regularly checked, and seems fine. Recent oil change, and timing checked. Igintion tested, and fine - good strong regular spark.

Change the seats ---- is this a machine shop thing? If I did have new heads when the engine was reconned - can these be repaired? is is worth it?

thanks for the advice...there may be some photos following when the repairs begin!

Cheers
E
2.1 DJ 1990 Caravelle (died and gone to heaven)
2.0 AGG (1997 ish) 1984 transporter LPG

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toomanytoys
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Post by toomanytoys »

Mmm
Seats are a mcahine shop only job...
you could slap on the head and see what happens..

Its difficult to determine what the problem actually is..

You are in chatham... I will be passing that way in a couple of weeks...

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ermie571
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Post by ermie571 »

Wow.....


there will be a HUGE mug of Tea waiting, or coffe or beer or whatever if you would like to drop in!!!

Bet you will be passing on the w/e of the 18/19 nov when I am away....

will pm you

Emma
2.1 DJ 1990 Caravelle (died and gone to heaven)
2.0 AGG (1997 ish) 1984 transporter LPG

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