DG1900 locks after approx 260 degrees revolution

Big lumps of metals and spanners. Including servicing and fluids.

Moderators: User administrators, Moderators

User avatar
maxstu
Registered user
Posts: 4474
Joined: 07 Feb 2008, 01:05
80-90 Mem No: 3946
Location: Margate

DG1900 locks after approx 260 degrees revolution

Post by maxstu »

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
MaxStu
1989 DJ 2.1 Auto Leisuredrive rusty bucket.
"Blissfully happy in your presence".

User avatar
937carrera
Registered user
Posts: 3599
Joined: 05 Apr 2015, 19:29
80-90 Mem No: 16333
Location: N Yorks.

Re: DG1900 locks after approx 260 degrees revolution

Post by 937carrera »

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

You can check that without dropping the engine

What's the history of the engine ?
1981 RHD 2.0 Aircooled Leisuredrive project, CU engine
1990 RHD 1.9 Auto Sleeper with DF/DG engine

User avatar
maxstu
Registered user
Posts: 4474
Joined: 07 Feb 2008, 01:05
80-90 Mem No: 3946
Location: Margate

Re: DG1900 locks after approx 260 degrees revolution

Post by maxstu »

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.
MaxStu
1989 DJ 2.1 Auto Leisuredrive rusty bucket.
"Blissfully happy in your presence".

User avatar
maxstu
Registered user
Posts: 4474
Joined: 07 Feb 2008, 01:05
80-90 Mem No: 3946
Location: Margate

Re: DG1900 locks after approx 260 degrees revolution

Post by maxstu »

What is the easiest way to check why engine locks?
MaxStu
1989 DJ 2.1 Auto Leisuredrive rusty bucket.
"Blissfully happy in your presence".

User avatar
Oldiebut goodie
Registered user
Posts: 7258
Joined: 18 Apr 2008, 01:19
80-90 Mem No: 11135
Location: Eastern Angle

Re: DG1900 locks after approx 260 degrees revolution

Post by Oldiebut goodie »

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.
1.6D 2019 VW T-Cross
200hp VW T6
1̶Y̶ ̶1̶9̶8̶7̶ ̶H̶i̶-̶t̶o̶p̶ ̶C̶a̶r̶a̶v̶e̶l̶l̶e̶
5̶0̶8̶d̶ ̶M̶e̶r̶c̶

User avatar
tobydog
Registered user
Posts: 1378
Joined: 07 Mar 2009, 21:03
80-90 Mem No: 6484
Location: Near Saarfend, Essex

Re: DG1900 locks after approx 260 degrees revolution

Post by tobydog »

Take the rocker box covers off and look at the valves?
Knowledge is power
1970 CU

User avatar
937carrera
Registered user
Posts: 3599
Joined: 05 Apr 2015, 19:29
80-90 Mem No: 16333
Location: N Yorks.

Re: DG1900 locks after approx 260 degrees revolution

Post by 937carrera »

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
1981 RHD 2.0 Aircooled Leisuredrive project, CU engine
1990 RHD 1.9 Auto Sleeper with DF/DG engine

User avatar
maxstu
Registered user
Posts: 4474
Joined: 07 Feb 2008, 01:05
80-90 Mem No: 3946
Location: Margate

Re: DG1900 locks after approx 260 degrees revolution

Post by maxstu »

Thanks. Did above. But cant get full revolution to isolated which valve is doing the naughtyy deeds.
MaxStu
1989 DJ 2.1 Auto Leisuredrive rusty bucket.
"Blissfully happy in your presence".

User avatar
937carrera
Registered user
Posts: 3599
Joined: 05 Apr 2015, 19:29
80-90 Mem No: 16333
Location: N Yorks.

Re: DG1900 locks after approx 260 degrees revolution

Post by 937carrera »

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) ?
1981 RHD 2.0 Aircooled Leisuredrive project, CU engine
1990 RHD 1.9 Auto Sleeper with DF/DG engine

User avatar
maxstu
Registered user
Posts: 4474
Joined: 07 Feb 2008, 01:05
80-90 Mem No: 3946
Location: Margate

Re: DG1900 locks after approx 260 degrees revolution

Post by maxstu »

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.
:ok
MaxStu
1989 DJ 2.1 Auto Leisuredrive rusty bucket.
"Blissfully happy in your presence".

User avatar
937carrera
Registered user
Posts: 3599
Joined: 05 Apr 2015, 19:29
80-90 Mem No: 16333
Location: N Yorks.

Re: DG1900 locks after approx 260 degrees revolution

Post by 937carrera »

:D :D :D

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
1981 RHD 2.0 Aircooled Leisuredrive project, CU engine
1990 RHD 1.9 Auto Sleeper with DF/DG engine

User avatar
maxstu
Registered user
Posts: 4474
Joined: 07 Feb 2008, 01:05
80-90 Mem No: 3946
Location: Margate

Re: DG1900 locks after approx 260 degrees revolution

Post by maxstu »

Yep! Off with her head. :ok
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.
MaxStu
1989 DJ 2.1 Auto Leisuredrive rusty bucket.
"Blissfully happy in your presence".

User avatar
937carrera
Registered user
Posts: 3599
Joined: 05 Apr 2015, 19:29
80-90 Mem No: 16333
Location: N Yorks.

Re: DG1900 locks after approx 260 degrees revolution

Post by 937carrera »

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.
1981 RHD 2.0 Aircooled Leisuredrive project, CU engine
1990 RHD 1.9 Auto Sleeper with DF/DG engine

User avatar
maxstu
Registered user
Posts: 4474
Joined: 07 Feb 2008, 01:05
80-90 Mem No: 3946
Location: Margate

Re: DG1900 locks after approx 260 degrees revolution

Post by maxstu »

In total agreement with your philosophy.

:ok
:ok
MaxStu
1989 DJ 2.1 Auto Leisuredrive rusty bucket.
"Blissfully happy in your presence".

User avatar
itchyfeet
Registered user
Posts: 12427
Joined: 23 Jul 2007, 17:24
80-90 Mem No: 12733
Location: South Hampshire

Re: DG1900 locks after approx 260 degrees revolution

Post by itchyfeet »

USB endoscope in plug hole or into sump may tell you something
get them for under 10 quid on ebay
1988 DG WBX LPG Tin Top
1989 DJ digijet WBX Holdsworth Villa 3 Pop Top
itchylinks

Post Reply