heavy knocking from engine.

#1
Hi, i think i have possibly killed my engine through simple stupidity, really do need some advise with this one.

just lately i have been getting a knocking noise from the engine on first start of the day, this only lasts for a second or two and then is ok, each and every start there after is fine.
Oil warning light always goes straight out, but oil pressure gauge would only read about 30 at best, but would drop off to nil after a few miles, ( engine running sweet).
To day i removed the oil pressure relief valve to check it was clear and spring ok etc, every thing looked alright. reassembled it all ( it was only apart for 30 mins).
started the engine, and had the heaviest knocking you could imagine, no oil pressure on gauge and oil warning light stayed on, switched it straight off.

Have i completely knackered my engine, going for a beer now to drown my sorrows!!!!!

Regards Steve
 
#2
Sounds like the oil system needs priming. Which engine is in your car? At first guess i'd say the knocking is big end wear so you probably haven't killed the engine, noise is louder only because there is no oil to damp it out.
 

jp928

Active Member
#4
The oil pump is driven by the end of the dizzy shaft. Mark the dizzy body and the side of its hole in front cover, unbolt its retainer, and remove. Look down the hole you should see a shaft end with a slot in it. You need to find something that can engage that slot (driver end?), and spin it clockwise with a drill or similar, until you get oil pressure. Refit dizzy, align the marks. Once you have pressure the oil pump will be full, and should hold oil until you start the engine. Others with direct experience will chime in I hope.
 

cobraboy

Well-Known Member
#5
Beware, fitting of a RV8 distributor can be very fiddly and time consuming. There is a long thread on here about a distributor 'growing in length' when removed and not going back in the engine !

It is tricky to align the distributor drive with the oil pump spindle when removed, and get the timing right, you have been warned.

I would suggest removing all the spark plugs ( easier ) fully charging the battery, and then cranking the engine over until you see oil pressure on the gauge. Re fit plugs and start.
It is probable that you just need to give the engine more time to build up pressure after taking out the relief valve.
When you have gotten oil pressure again and know how to do it, you can go back to the low pressure issue.

You can remove the relief valve again, take spring out of the piston and slip in a couple of small thin washers, replace the spring and valve.

This will gain you a few psi and will help your tired engine live a little longer.
 
#6
Hi, thanks for the advise, heeding the warning about refitting the dizzy, i have tried the other method, ie removed all plugs, spin the engine on the starter, -- result -- nothing, not even a flicker on the gauge, been spinning it over for ages, getting worried about the starter burning out

regards Steve.
 

quattro

Administrator
Staff member
#7
I would lift the dizzy out, but before you do, mark the body as JP says by applying a bit of tippex to the body and a bit on the timing cover so you can replace it in the same place. Then unlip and remove the cap, then mark the dizzy body where the rotor arm is pointing. Take note that when you pull the dizzy out that the rotor arm will turn slightly (about 30°), mark where it's pointing after pulling it up too. This will help when putting it back.

Spin up the pump for a few seconds until you get some pressure. If you haven't got any within 10 seconds, you may have a problem :confused:
 

colnerov

Well-Known Member
#8
I would lift the dizzy out, but before you do, mark the body as JP says by applying a bit of tippex to the body and a bit on the timing cover so you can replace it in the same place. Then unlip and remove the cap, then mark the dizzy body where the rotor arm is pointing. Take note that when you pull the dizzy out that the rotor arm will turn slightly (about 30°), mark where it's pointing after pulling it up too. This will help when putting it back.

Spin up the pump for a few seconds until you get some pressure. If you haven't got any within 10 seconds, you may have a problem :confused:
Hi, I would add to that to make a note of the pump shaft slot orientation so it can be returned to the same position so the dist can engage with it again.

Colin
 
#10
I had a problem with no oil pressure on start up after leaving car idle for some weeks, when I was working away from home. Had to prime the oil pump. Instructions in Haynes or Rover work shop manual:-
Open oil pump and pack rotors with Vaseline. Close pump up and start engine as normal. Always worked. Then I would change the engine oil and did not trust contamination with Vaseline.
This always happened with oil filter sold by local ' expert.' went back to using oil filter from Halfords, then from Rover supplier. never had the problem again.
N.B. You need a special Torx socket to open the oil pump. Can be done with 3/8 socket jammed over stud. Accessibility of oil pump is a pain unless you have a ramp. need to start the engine to drive the car onto a ramp?
 

colnerov

Well-Known Member
#12
Hi, Yes, the other name for vaseline is petroleum jelly so it will just be absorbed into the oil. No harm no foul.

The bolts heads for the pump face are 12 point 5/16" AF or 8mm, (spit) sorry Harvey. You can get a 12 point socket on four (I think) and a ring spanner on the remaining.

Colin.
 
#13
Hi, first of all, many many thanks to all who gave very helpful advise with regards my initial problem, how bad my engine was knocking, i was sure it would be terminal.
However after reading the helpful posts on the forum, i went to a place ive never been before,
First tried to get some oil pressure by taking plugs out and spinning on the starter, result -- not a flicker and warning light stayed on.
Secondly ( very new ground for me ) remove the dizzy, taking in to account of all the advise ref markings etc, made up a temp tool to try and spin the oil pump, ( bit of tube that sat over the shaft, large screwdriver on drill inserted through tube and in to the slot) Wife in drivers seat to watch warning light and gauge, holding my breath, span up the oil shaft, about 3/4 seconds later felt the pressure build on drill, warning light out and nearly 30 psi on gauge.

Part one completed, we have pressure, but will it run?

Carefully replaced dizzy, ( i had practiced this a few times prior to spinning the engine), connected every thing up again,

Turn the key, engine fired first time, warning light straight out 30 psi on gauge, and no heavy knocking, let it warm up slowly and settle down, all seems quite good, may need to check and adjust the timing later, but for now i am over the moon.

As before many many thanks for all the helpful advise. Regards a very relieved Steve
 

colnerov

Well-Known Member
#15
Hi, Yes, It's good that you let us know how it worked out. There have been occasions when people ask questions, we answer and then never hear again. It helps that we hear what did a didn't work. So thanks for that!!

Colin
 
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jp928

Active Member
#17
Glad thats solved, well done! It has surprised me before how much load the oil pump can give. Helped a mate work on a Chev small block once - glazed bores. Before trying to start we spun it with plugs out, and at first it went very well, but the slow down when oil pressure came up was quite marked.
 
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