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Discussion Starter · #1 ·
So this is the third or fourth head gasket I've changed on a K series engine but the first one that hasn't started after I've finished.
The car sounds like the timing is out, so I checked and the 90deg BTDC is confusing me a little. There is the 12o'clock mark on the crank casing, then a 'TDC' mark about 35deg before it, plus some other markings, I assume for if you want to retard the timing for any reason.
With the cams both 'exhaust to rear' of engine (as per Haynes and engine manuals) my engine was timed to about 90deg before the TDC mark (the notch on the aux crank pulley was at about 8o'clock. I disconnected the belt and advanced the crank round to 12o'clock, with the cams locked in exh to rear position. I had rods in to check piston positions, and at 12o'clock the pistons were all level - as is apparently normal for Rover/MG TDC???
It felt like a massive move for the crank with the head connected, but that was how the book said to time it, so I did. 2 full manual rotations later, no knocking, no problem.
But the car still won't run.

I just want to rule out other possibilities before I go in and look at the valves to see if they were damaged in the crank advancement.

Any ideas?? The car was running fine prior to the head gasket issue (only changed because coolant was running low and the car temp was creeping up) and I re-assembled it to the same timing as it has come apart.
NB: The chambers were full of coolant so it definitely was a required repair!
 

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mgf
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if you take all the spark plugs out when you turn the crank over by hand does it move freely? also add photo of the timing marks on the cam sprockets and also the crank so we can see what its set to when the notches on the cam pulley are lined up horizontally. also is there enough petrol? whats the fuel gauge saying.
 

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'06 MG ZR +120 (HQM) '04 MG ZR 105 (IAB)
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With the cams in the correct position ('EX' to rear as you put it), the crank pulley should align with the mark on the lower cam belt cover which is slightly forward of the '12 o'clock position. If the crank pulley is removed, there are two shallow holes on the lower cam belt pulley which should align with the cast mark on the block (also just forward of 12 o'clock).

Ignore the 90 degrees BTDC mark, it is not relevant for setting up the timing.

Assuming you have the crank pulley marks aligned, and the cam pulleys with 'EX to rear' as they should be, have you checked that the dowels in the end of the camshafts are in the correct slot on the cam pulleys? (rear one in the 'IN' slot, front one in the 'EX' slot).

Also check that the crank pulley and cam pulleys are synchronised at the correct stage of the cycle - it is possible to have all the marks cvorrectly aligned, but the crank pulley 360 degrees out of sync (ie one full revolution of the crank from where it should be and the engine will not even attempt to start as the valves will be open at the wrong stage of the cycle).
 

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rover_600
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This is the dreaded 4 stroke problem, perhaps Sabb had it right in the 1970s when their cars were 2 stroke. This bit is very good advice as you can have the timing appearing to be correctly set but you can have one of the cams 360 degrees out of sync. God bless the K series engine.
 

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Discussion Starter · #5 ·
Thanks all.

I haven't tried turning it over without the sparkplugs but it moves well with them in. I tried topping up the fuel because it was on the red line (tried this before changing the timing).

I haven't removed the crank pulley. I figured the outer notch should line up with the main crank pulley underneath? Although that was a potential next check also.

I have debated whether I'm a full turn out, I just don't know how it would be?! The crank wasn't moved at all throughout the head gasket change, and the cams were replaced as they were removed. Unless it's the cam's misaligned on the dowels? You can see the dowels in the picture below. Sorry the crank is blurry - it's not an easy shot to get!

136370
136371
 

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mgf
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all looks spot on, i would bet fuel, i had quarter tank when i did my head gasket, wouldnt start after i put it together, i put 2 gallons in of petrol after a member here said fuel and it started straight away, worth a try as i was like you, i was thinking about being 180 degrees out and questioning everything i did.
 

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rover_25
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It won't make any difference if the crank is 360 degrees out, the rotor arm is on the cam in the early ones and the later ones are wasted spark firing 1 and 4 together and 2 and 3 together.
 

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MG ZT, Rover 25
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Have you checked basics: sparks, fuel, exhaust and induction are fine? Cables, connectors pipes etc.
 

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rover_400_95_99
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Silly question, but have you checked the ignition and the ignition cables? Are the cables correct connected? You don't have cable for cylinder 4 in cylinder 3 or something like that? Is there a spark from every spark plug when you rotate the engine?

Best regards!

Martin
 

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rover_400_95_99
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This is the dreaded 4 stroke problem, perhaps Sabb had it right in the 1970s when their cars were 2 stroke. This bit is very good advice as you can have the timing appearing to be correctly set but you can have one of the cams 360 degrees out of sync. God bless the K series engine.
Hi alanaslan!
I have never heard of the car Sabb even though I am from Sweden :D. But Saab had some twostroke cars and also rally cars, if you wan't to hear and see one in action search on this pharse on Youtube: "Saab Sport 1965 2-stroke Rally Maximum Attack!".

Best regards!
Martin
 

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rover_600
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Hi alanaslan!
I have never heard of the car Sabb even though I am from Sweden :D. But Saab had some twostroke cars and also rally cars, here is one, Saab Sport twostroke model year 1965:
.

Best regards!
Martin
Big fingers, saab is of course correct Thanks Martin, they used to make aircraft as well. The last Saabs sold over here were Vauxhall built. and shared many parts
 

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rover_600
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Did the little air cooled Citrons which were 4 stroke not drive their points off the crank shaft meaning that every time a piston approached TDC both spark plugs sparked meaning the car only got it right half the time?
 

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'06 MG ZR +120 (HQM) '04 MG ZR 105 (IAB)
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Big fingers, saab is of course correct Thanks Martin, they used to make aircraft as well.
They were manufacturing aircraft some time before making their first car - the company name (Svenska Aeroplan Aktiebolag in Swedish, for which SAAB is the acronym) translates into English as 'Swedish Aeroplane Company Ltd'.

Totally off the topic of this thread, but relevant to the forum - when SAAB first moved away from the two stroke engines in their cars with the SAAB 99 in 1968, it was fitted with a 1706cc version of the Triumph 'slant-4' engine (later used as in the Triumph Dolomite and TR7) imported from the UK for the first year or so of its production. After SAAB merged with Scania-Vabis in 1969, they started manufacturing the 1854cc version of the engine themselves in the Scania factory and redesigned and improved it themselves to become the SAAB 'B' which they fitted to their cars until the early 1980's.
 
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