Hello everyone my names Chris, from Adelaide, South Aus.
Ive finally conceded to asking for assistance regarding my XJ6.
Ive been tinkering away for months now, reading all the bits and pieces i can scattered all over the internet etc, but ive finally come to needing to ask for help.
April last year i picked up a old 77 model XJ6 S2 that had been sitting at a farm for a while. Long story short it needs some love and work to get it back on the road for a reliable weekend cruiser through the Barossa.
Its got a semi colourful history to which i will discuss at a later date, but the short version is im the 4th owner since new and the cars only got 33xxx KMS on it.
Im having issues getting the engine to run correctly, it needs the BW65 auto rebuilt, interior tidy up, aircon system updated and pump reinstalled, bit of paint and panel.
The auto i will sort out as i have the complete rebuild kit waiting to go in, paint and panel ill do over time, interior im already onto cleaning and retrimming, aircon will be a next summer issue, but my main concern is this bloody engine!
In not new to engines, ive had many older vehicles and im not shy to working with the classics, SU carbies, etc etc.
So to date, the engine. Upon purchase i was told it was a āgood engineā and āRuns smoothā to which were alarm bells that someones been fiddling. Fast forward to inspections, someone had redone the original dizzy with new points, coil and sort of new wiring, old plug leads, new plugs (not correct gap and range) and the head looks like it had been off at some stage in its life.
The dizzy i have exchanged and replaced with a s3 electric dizzy, new leads and new plugs.
I checked the engine timing today and it appears all to be within spec, since the head had been off. I did make adjustments to the upper timing chain tensioner, as i do believe it was over tight which as a result was rotating the intake cam minutely advanced. Wouldnt have said it was 90 degrees to the rocker flange.
The cams are what id call the s3 style, with the 4 bolt cam gears.
I checked valve clearances and it was on the higher side of tolerance, but were all equal.
Ive completely rebuilt hte SU carbs, theyre HD8, which i believe were S1 carbies. All good there, rear carby diaphragm was shot, but the rest of the carbs were actually in pretty decent order. Ive removed and disables the cold start mechanical valve as this was flogged. was more of a fuel leak then anything beneficial. I can always rebuild it and reinstall should i get the engine running right to start with.
So symptoms, hard starting, not smooth running, backfired through carbs when approaching 3k rpm, sluggish to rev ( i have no reference as what is deemed normal), overall its like as if the timing is way off and the engines struggling.
The timing has been set to 8 degrees, sometimes as advanced as 12 degrees, but again after a lengthy time inspecting and having even the old man check it out we determined that was all set (for now - to at least get it started and half running)
Ive done a comp test and all but one cylinder were equal, the odd one out did eventually come up to compression equal to the others. Suspect it was from sitting around too long.
Im now at a bit of a loss as to what to aim for next, its not an overly complicated engine and its whats becoming most frustrating is that i cant put my finger on whats holding it back. i was nearly confident it was a cam timing issue that someone who did the head job had reinstalled it wrong but after todays checks im now lost.
Has anyone got a whisper of any idea to trial, im nearly tempted now to remove the whole engine and pull the front end off and double check timing is all 100%.
Also has anyone got a decent timing guide, something i can print out and work through.
I cant find the workshop manual i once found online anymore, any help would be greatly appreciated!