AEC 505 fuel pump timing

Mursal · Mar 28, 2017

The head gasket going, would have nothing to do with the bent push rod/valve. Even if it took in water I never heard of water/coolant bending valves/push rods? But that's the only link between head gasket failure and bending valves/push rods, that I can think off. Usually head gasket failure is due to over heating/ head not tightened down properly/incorrect fitment of the head gasket. Gasket to light not heavy enough.

Going to ask silly questions, now:
Did the three things fail together?
Exhaust or inlet valve?
Only one valve and one push rod?
The gasket failure is at the back of the engine Pete, furthest away form the fan?
No 6 cylinder had the bent valve and push rod, right beside the gasket failure?
And the valve and the push rod are linked, or on different valve trains?
Did the piston come up and close the valve, you will see (hopefully) a mark on the top of the piston?

Cab-over Pete · Mar 28, 2017

I'm going to write something silly now:

Previous to pulling the engine stop she was running beautifully. Obviously chuffing, but nothing to suggest the bent parts.

Exhaust valve, just one valve and one push rod.

Gasket failed around number 5. Not sure if the bent parts were from number 5, I wasn't there while Matt took it apart.

I think the valve and push rod were together.

No contact made by piston on valve at all.

Mursal · Mar 28, 2017

That's a pity ................

The valve push rod sounds like valve timing might be out a touch, but I'll ask a lad that built them back in the day.
Dont think there's timing marks on the camshaft, but I'll ask him ............
But you have to ask yourself what bent them (push rod and valve)
On first thoughts it can only be the piston .........

Remember a lad dropped from sixth into what he thought was fifth going down a hill just to hold her back a bit .........
But got third instead, over revved and bent all the valves and broke a rocker shaft ............

Cab-over Pete · Mar 28, 2017

There are no timing marks anywhere at all.

I think Matt was worried he had something wrong but if he had mistimed anything then surely it would have shown up immediately upon first starting.

We've been out in it several times, been round the block a few times, probably 12-15 miles. The engine must have been running for two hours at least.

Mursal · Mar 28, 2017

Yes I agree you would expect it to show up straightaway after starting, very strange.

Mursal · Mar 28, 2017

You might have had a tight tappet, holding the valve open later than normal.
That would explain why only one got caught bending the valve and push rod.
Especially if the head bolts were just after being pulley again, that would upset the tappet clearance.

essexpete · Mar 29, 2017

I wonder if the valve got tight in the guide with some micro sh!t from the engine standing then with the engine warming up and moving some crud? Would that be possible?

Cab-over Pete · Mar 29, 2017

Engine was totally dismantled and rebuilt, new valve guides included and new exhaust valves.

Cab-over Pete · Apr 25, 2017

Back on the road!!!! Thanks all for advice and ideas, very much appreciated!

I had a smile a mile wide out on test run. Just need a bit of practice at the 6 speed!!

essexpete · Apr 25, 2017

What do you think caused the problems Pete? I remember Dad and his driver both using 2 hand to find reverse.

Cab-over Pete · Apr 26, 2017

I really don't know. It's early days yet because our problems came after about 15-20 miles running, but seems fine just now.

Funny about the reverse, it was a one handed job before all the work, but definitely two hands now!! The adjustment range is very fine.

Thanks for your help.

Cab-over Pete · Jun 7, 2017

Now Then!!

Good day today, took her for an MOT test, passed first time!! Inspector said he's done 4 year old trucks in worse shape!

I'm chuffed with that. Done a few miles today. Need more gear changing practice.

Thanks again for all your help.

Cheers, Pete.

Netherfield · Jun 7, 2017

Gearbox eventually will become second nature. Like you say it just needs practice

AV 505 · Aug 31, 2022

AEC 505 with a DPA pump,
Remove the side plate, see letters marked on the rota.
Connect number 1 outlet pipe to an injector pop tester, pressure up to 30 atmospheres, turn quil-shaft slowly
until the pressure drops and the pump locks up, the pump is now trimmed.
Inthe side of the pump you'll see a line and a letter. Scrib a line on the circuit inside the body to line up with the line on the rotor,
Set flywheel to 15' btdc, fit the pump and line the pump line and letter with the scribed line.

Cab-over Pete · Aug 31, 2022

Cracking, thank you.

This thread was 5 years ago, but much appreciated.

I still have the lorry, enjoying it very much and running well

Netherfield · Aug 31, 2022

Have you mastered the gearbox yet?

Cab-over Pete · Aug 31, 2022

Yes, much better.

It’s a treat once warmed up.

essexpete · Aug 31, 2022

Cab-over Pete said:
Yes, much better.

It’s a treat once warmed up.

Can you do an in and out cab video sometime?

Cab-over Pete · Sep 1, 2022

I can try, but with my tech skills it might be quicker if you walked here and had a look yourself!!

You’ll have to remind me, she won’t be out of the shed for a couple of months at least.

AEC 505 fuel pump timing

Member

Member

Member

Member

Member

Member

Member

Member

Member

Member

Attachments

Member

Member

Member

Member

Member

Member

Member

Member

Member

0 %

Up to 25%

25-50%

50-75%

75-100%

100% I’ve had enough of farming!

Share this page