Bend pushrods! :-(

P

Preben

New Member
Today i got my V8 started (it had been standing many years) and it did not run on all cylinders, after i checked everything else i took off the valve covers san discovered a bend pushrod in every side. :cry:

What is most likely to have caused this?
 
Most likely the valves were stuck in the guides, and when the pushrod tried to open them the pushrod bent as it was the weakest link in the chain. Check that none of the valves are bent, any valves that were seized in the open position may have been hit by the pistons.
 
But to check for bent valves i probably need to lift both cylinder heads. Is there a possibility that the lifters were emty and the balls on the rods just fell out and got jammed? They almost looked like this: ? and both looked exact the same. Now i have straightened them as good as i could, then i can make a compression test tomorrow.
 
You dont need to lift the heads to check for bent valves, you can either do a compression test as you suggest, or remove the rocker shafts, (as you already have to get the pushrods out) and lay a straight edge along the tops of the valves, the bent ones will be a noticable amount lower than all the others which will all be near enough touching the straight edge.
 
Another possibility with a high mileage engine would be a shot primary drive chain and sprockets, allowing the chain to slip a tooth or two. That would allow valves to contact pistons which might well lead to this. But if so I'd be surprised if you could start it! - the timing of the distributor would be out as well as the cam timing.

Chris
 
Its alive! :D

No big problems, but i found two more bend pushrods, that makes it four.

I doubt that the primary drive is shot, the car has only about 80.000 miles on the counter.
 
80000m is probably more than the averagre life of a camshaft , chain and gearwheels
See if the timing drifts when you use a strobe light , if so the chain is worn
 
DaveHerns said:
80000m is probably more than the averagre life of a camshaft , chain and gearwheels
See if the timing drifts when you use a strobe light , if so the chain is worn
Click to expand...

OK, i do that later on, its standing in snow and mud now, the plan is toget the brakes to losen so i can move it.
There is no rattle from the chain though.
 
Hello Preben,

Dave is spot on when he says that 80,000 miles is more than sufficient for the timing chain etc to requre replacement. The chain won't rattle as the timing wheel teeth are made from nylon.

Ron.
 
Its on the to do list now, i just have to buy it. There is two kits on ebay now: a NOS with nylon gear including distributor gear and another one in steel without distributor gear, i suppose the steel gear is best?
 
With distributor gear? That isn't part of the primary drive, it's part of the camshaft. There are two types of front end and cam for the Rover V8. Early cars, like ours, have a short prmary drive casing, and the distributor and oil pump are driven directly from the cam. Later, "Serpentine", engines have a much deeper casing with no distributor/oil pump drive on the cam. But the chain and sprockets are common to both types. You really want to buy a "duplex", ie double row, chain with steel sprockets. You can also get these with or without a vernier adjustment for getting the cam timing absolutely spot on. If changing the cam, you need to buy both cam and a new set of followers (The old followers will have absorbed hardened metal from the old cam and will destroy the new one in no time flat). A bit of an opportunity to buy an upgraded cam - there's really a choice of three unless you want to make your engine into a temperemental race engine. Try Rover 3.9 cam (ie suitable for the early range Rover Classic 3.9, not a later Serpentine 4.0), RPi/Piper RP4 or Real Steel "stump puller".

Chris
 
I'm sure I have a spare standard timing chain with crankshaft and camshaft gears in my box of v8 bits in the garage if you're interested? They were bought brand new and trial fitted before being removed to fit a duplex timing chain kit. Let me know if you're interested?
 
chrisyork said:
This is the top of the range vernier duplex timing set:

http://cgi.ebay.co.uk/Piper-Rover-V...arts_Vehicles_CarParts_SM?hash=item2c53b71bb6

But I'm pretty sure you actually need all of this:

http://cgi.ebay.co.uk/Standard-Rove...arts_Vehicles_CarParts_SM?hash=item2c53a1b770

Regards

Chris
Click to expand...

I´m not ready to buy new cam and lifters and those things att the moment, such thing will be on the list if/when i rebuild the engine in the future, i just want to get the car on the road and fix things wintertime and when the money and motivation is there, i have some other cars which need my attention as well.
 
It's not easy when you have other calls on your finances and have to prioritise

The chain won't rattle as the timing wheel teeth are made from nylon.
Click to expand...
- the problem is that the teeth fall off

When I changed my timing chain , it was very slack but the teeth were all intact
 
sowen said:
I'm sure I have a spare standard timing chain with crankshaft and camshaft gears in my box of v8 bits in the garage if you're interested? They were bought brand new and trial fitted before being removed to fit a duplex timing chain kit. Let me know if you're interested?
Click to expand...
I think that the smartest for me to do is buy something in steel, thanks for th offer though.
 
Do you have an opinion yet about the state of your camshaft? Do all the valves operate with the same amount of lift when you motor the engine? The reason I ask is that when you change the timing chain set it is only another 1/2 hours work to change the cam as well. If you come back to change the cam later you will have to repeat all the work already done to change the timing chain.

Chris
 
I havent thought so much about that, are these camshafts so lousy quality? I´ve owned cars with 150k miles on the clock without problems other than blown head gaskets (Ford Scorpio and Jaguar XJ40) and these camshafts were ok.
 
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