Finally got around to installing the RMW dominator cam on my 2006 JCW. I took off the valve cover and discovered a broken intake valve spring on cylinder 2. It could have been broken for awhile or more recent. I have 84K on it. I have been tracking it and have not noticed a loss of power. I'm planning on just replacing that spring without pulling the head. Should i pull the head and do all of them?
If I do just the one, can anyone recommend a valve spring tool that will work? It's super tight in there?

 

It is hard to say why the spring broke, but I think I would pull the head, replace the springs with tested ones. A broken spring can happen, but it can also be several poorly heat treated, in a lot, which may include others in your head!
It really is up to you, how you feel about it!

 

Reading a lot of posts, it seems broken valve spring is rather common with R53s. Pulling the head is a lot more work and expense. The up side is you can replace all the valve guide seals much easier.

If you try to avoid pulling the head, it might be a good idea do a compression test first to see if the valve have been seating poorly. Good it is on a intake valve rather than exhaust that is a lot hotter. I would do a test before and after to gauge the health of that valve, guide, and seat.

 

I think I will put in a new spring in without pulling the head. Check the compression and do more work if necessary.

 

I have a grab type compressor since high school , but that looks awfully tight. May need to remove the spark plug tube to get more room.

 

I found my USA made grab type compressor today looking for tools. You are welcomed to try it.

 

Thanks! I just bought from amazon. Looks like the one in the pic you posted. If it doesn't work I will get in touch about borrowing yours.

 

I got it done with the tool above. It was REALLY difficult to grab enough spring to get enough compression to get the retainers in. Took me about 2 hours and a lot of swearing. To keep the valve from falling into the cylinder I pressurized it to ~45 psi.

 

That's good news. I found most often the grab type compressor is hard to use too, as you cannot get to the last coil. Then often the retainers are wedge tight. The lever type compressor that dealer has generally are not universal.

 

I would do all the springs, you never know if it failed due to a component issue or from a use issue.

If it is a component issue then adding a big cam can cause the wear on the rest to be accelerated.

 

I'm going to tell myself that it was just a bad one in a batch. Maybe in the fall I'll take it apart...

 

That is my opinion too. I have read many single broken valve springs. I would not throw money and labour at it without any substantiated evidence.

 

The problem I have with this thinking: If another one goes and takes out a piston, it can toast the whole engine. I comes down to what risk you are willing to live with!
If I ever find a broken valve spring in my engine, they will all be replaced, as they were manufactured at the same time and the heat treatment and draw back (temper), could be flawed. One broken spring is a warning sign!
Yeah, it is a bummer, but you need to deal with it or not!
Itsme Wayne a Retired tool and die maker, with much heat treating experience.

 

While I know where you come from on heat treating and manufacturing batches. By throwing around a credential only ends our debate fast. Case in point, there are economics, mileage of the car, risk-averseness of the owner, down time etc to consider. Most of us know this is an interference valve train engine.

 

I'm all for the "while I have this apart already maybe I can save myself some trouble long term" type of thinker