Club 80-90 Forums

1985 DG 1900 early version cooling. Can only rotate engine 300 degrees on timing wheel either clockwise or anti- clockwise before its locks. Whats the most obvious issue before l pull engine from van.
Regards
Stuart

Initial thought, dropped valve, piston contacting static valve head ?

You can check that without dropping the engine

What's the history of the engine ?

Bought as a non runner knowing engine fault. Working up to Dec 2017. Big backfire through carb which melted pancake plastic on LPG. Have post 1985 spare engine. But trying to isolate and fix problem with engine in situ.

What is the easiest way to check why engine locks?

Bent valve would be my first thought.
Cover off to find which valve isn't working on the rotation that you can do. Or screwdriver/steel rod stethoscope on the head and you should be able to hear any contact.

Take the rocker box covers off and look at the valves?

Plugs out, rocker covers off.

Initial inspection to see if there's a broken valve / valve spring

Try and identify which cylinder it is by seeing at what part of the crank revolution the engine cannot be rotated

Thanks. Did above. But cant get full revolution to isolated which valve is doing the naughtyy deeds.

Which part of the crank revolution can you not access (use the fan pulley as reference, maybe mark TDC with paint if not already done) ?

Using Tdc marker on crank pulley wheel. Have found one valve stem badly damaged and corresponding valve adjuster chipped on end
Too dark to photo but reckon head off and inspection. Hopefully isolated to head only as engine still rotates as mentioned above.

Off with her head then, see what the damage is.

I bought a Polo with an issue. Turned out one of the timing belts had stripped. Off with her head and she only needed two valves..... less than £8 each at ECP

Yep! Off with her head.
Or Ive got a spare working 2.1 on carb but not certain if costly to adjust plumbing from pre 1985 to post 1985? First time lve played with pre 85 style DG.

I don't believe it's that much work to remove /refurb one head and then you will have two working engines.

I haven't worked on a WBX, but from what I have read I believe it is possible to do a head with the engine in situ. Tricky, but possible. Itchyfeet among others will know.

You should at least remove the head in situ, being optimistic that you can fix the engine without having to remove it. If you can't, you've just spent a bit more time to get to the same place.

In total agreement with your philosophy.

USB endoscope in plug hole or into sump may tell you something
get them for under 10 quid on ebay