Anybody know a source for good quality rocker arms (1994 D1 3.9L). Any recommendations? Steel vs aluminum?

I found the knocking was a loose pushrod cup for #6 EX. Engine running, stethoscope on the rocker shaft pillar bolt pinpointed #6 and visual sync'd with exhaust. Small screwdriver found the cap was very easy to move.

These rocker arms are "new" aluminum (6 years in engine, about 16,000 miles) from Atlantic British. Part 602154 (left hand) was the bad one. Telltale sign is with the three crimps that fix the cups in place. On the bad one, only two of the crimps look solid, the third barely hit the aluminum edge, compared to the rest of the arms. Several others have crimps that are not quite positioned well (both left and right hand rockers, 602153 and 602154). So, I want to replace the lot.

 

john Craddock shows alloy and steel options. I think I would call Will Tillery and try to find some good used genuine rockers.

 

Thanks, Walt. Will has a "clean used set" for $50. Decided to order a single new from L8, description says OEM aluminum, $12.

Researching found an interesting approach to use steel on EX and aluminum on IN. Logic was higher force needed to open EX to overcome cylinder pressure. That is probably more applicable to souped up hot rods, not my truck. Found the Forum old thread about the pushrod cup coming loose, Disco Mike was there. Other online discussions liked steel arms from Federal Mogul. I also found mention that the cast steel arms, being a bit porous, have a self-lubricating property. So, I was tempted to go steel. Maybe, if I am unlucky, next time.

 

New rocker arm in. Nice and quiet now. The part number was 602154G, in a BritPart box. Attached photo shows the weak crimp that allowed the cup to spin/rattle.

Defective rocker arm, pushrod cup spins, weak crimp shows on top

 

I'd be interested to know how this goes longer term. Given your active participation in these forums, I am sure you are aware Britpart doesn't have the best reputation.

 

Thanks, Walt. So far so good. I changed the oil/filter and have taken a couple break-in drives. No leaks! Coolant back to level. I did not take a photo of the new arm, but there are three crimps that are nearly square shaped compared to the long rectangles on the defective one. Each square is pushed in deep, compared to the rather shallow defective arm, so I felt confident with the quality. And it fit on the shaft as tight as the others.

Of the other rocker arms on this right side, one or two others had square crimps, most had the rectangular crimps like in the photo. Maybe different production runs? Or a mix of BritPart and All-Makes (the set came from AB)? Probably the same manufacturer in China (box says Made in China). The three grooves in the bore were not in the same exact locations as the old one, but appeared to be the same width and depth. Castings had a few minor differences. The warranty from L8 is 12 months or 12k miles. Over all, I feel good about getting 6 years and 16,000 miles on this defective arm even though it was a PITA and caused me to chase my tail for a long time worried about ticks and exhaust leaks. I did not change the whole set because the other arms are worn in well and the rest all had crimps that were a bit deeper and straighter than the defective unit. It's nice to have a smooth quiet engine again!

 

Forgot to mention the BritPart part number ends with G. Usually that means Genuine Land Rover part, and it was advertised as OEM. Does BritPart make parts for Land Rover? The box was not a Land Rover box. I am a bit confused. Did I get the real McCoy or not?

 

I think the lines are blurring in regards to LR parts manufacturers these days. I ordered a Hardy Spicer rotoflex from L8 recently that also had a G after the part number. The part arrived in a Britpart XS branded box that stated original GKN parts.