Distributor fitting

#1
I have recently purchased a mgb gt 1977 that has been converted to a rover sd1 v8. I brought it as a non runner and hey presto it's still a non runner. It has been sat for many years so was slight seized but engine is moving. I've stripped the fuel pump and that now works, rebuilt the starter which worked but I've decided to replace it as it didn't have the power to turn the engine very well.
I have also brought a distributor which isn't original but does fit and is from a decent company. I have tried turning the car over and it keeps trying but with no joy.
I am wondering the correct way of fitting the dizzy as I think it may be out.
I have had to spin the distributor 180 degrees as the vacuum and module are opposite sides so I can't alter the timing much before one of them hits a pipe or engine. After I fit it I read somewhere about the oil pump could be out. Anyway my question is, starting from scratch and finding tdc what is the correct way to fit it? Can the oil pump be fit anyway? Please help as I'm out of ideas and I'm no mechanic
 
#5
I'm no expert either but have coaxed a few old v8s in to life. As long as you are sure that the cam timing hasn't been messed with i'd remove no 1 spark plug, rotate the engine to TDC on the compression stroke of no 1 (you will feel the pressure over the plug hole) and then recheck that the rotor arm is pointing to no 1 HT lead on the cap. If not, adjust the distributor and try again. If you need to remove the distributor and re-seat it to get the adjustment then do that.
Just another thought, make sure that the distributor is all the way home. There should be no gap between the base of the distributor and the front timing cover.
With regard to the oil pump, the distributor is driven via the gear on its shaft, from the camshaft. The oil pump is driven in turn by the slotted key in the very base of the distributor. The oil pump does not need to be timed or synchronised in anyway to the rotation of the engine so you can't upset the oil pump as long as the distributor is fully home.
 
#6
I definitely have it at TDC and the rotor arm is on number 1. The distributor is definitely fitted correctly but still no joy. I have had someone turn it over and ive tried the timing but no go. It does try but if i don't try it in a couple of days its like its never wanted to try.
i Have fitted electronic ignition dizzy so do you think it still needs the ballast wire?
 

roverp480

Active Member
#9
Cylinder should be on a compression stroke with both valves closed at TDC, If its 180 degrees out it will be at TDC but the exhaust valve will be open .
 

colnerov

Well-Known Member
#11
Hi, Yes, but that puts the crankshaft on TDC, you need the camshaft on No1. The crankshaft turns twice to the camshafts once to complete a firing sequence. Take the rocker covers off and check what the valves on No1 and No6 are doing, you need the rockers on No6 'on the rock' (one closing and the other opening) as you turn the crank backwards and forwards, this makes sure the valves on No1 are closed.

Colin
 

Cafcpete

Active Member
#12
Hi, Yes, but that puts the crankshaft on TDC, you need the camshaft on No1. The crankshaft turns twice to the camshafts once to complete a firing sequence. Take the rocker covers off and check what the valves on No1 and No6 are doing, you need the rockers on No6 'on the rock' (one closing and the other opening) as you turn the crank backwards and forwards, this makes sure the valves on No1 are closed.

Colin
Or take the plug out and cover the hole with your finger whilst turning the engine. You finger should get pushed away with the compression once the valves are closed.
 

harveyp6

Well-Known Member
#16
Well if it's 180 out, then swapping the leads over might get it running, and it's easy to put back if not, and once it's running the dizzy position and timing can be sorted then.

I agree with you last comment, and it probably isn't the easiest thing to get help with over the internet either.
 
#17
Thanks for your comments. I will try the above and see how I get on. I just want to get it started to see if it is all ok then I can strip it down, clean it up etc
 
#18
Hi, Yes, but that puts the crankshaft on TDC, you need the camshaft on No1. The crankshaft turns twice to the camshafts once to complete a firing sequence. Take the rocker covers off and check what the valves on No1 and No6 are doing, you need the rockers on No6 'on the rock' (one closing and the other opening) as you turn the crank backwards and forwards, this makes sure the valves on No1 are closed.

Colin
I have tried this just rocking it back and forthe and the pistons moving up and down but I can't see any movement on any valves until the rotor arm is 1/4 way around the dizzy and then I see 1 valve on number 1 go down. Not sure which one is the exhaust one. I've only ever done this on a little 1600 vw beetle engine so it's a different ball game.
 

cobraboy

Well-Known Member
#19
With a little car like an MGB it is very easy to pull forward by hand. Take out number 1 spark plug, put the car in 4th gear stick your finger in the plug hole and pull the car forward. You will eventually feel compression build, then you know number 1 cyl is coming up to TDC on its firing stroke.
Carry on pulling car until crank pointer and mark on damper align at 10 degrees before TDC.
Now all you want is the rotor arm to point at the metal post inside the distributor cap that has number 1 spark lead on it.

The timing will be set good enough to start the engine.
 
#20
Ok so I've looked again and I was correct when I installed it. I've had the rocker covers off and tested it all and I'm definitely at tdc, Still no joy though. I've tested and have a really good spark although the car is still turning over slowly. My only other thought could be the carbs. I have had them off and cleaned them up but never known how the pistons on them work. They used to be seized when I first got it. I have them moving freely and have put oil in them but now it takes some force to get them up? Maybe a post for another page though
 
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