Broke the timing belt this weekend

#1

Running a DE at VIR. Question: the engine is probably destroyed, right? I can get a used motor for $1,150 including shipping. Does it make more sense to just drop in a used motor w/ new belt and put in the crank scraper or should I take the time to pull the head and check it and the pistons for damage? Any thoughts would be appreciated.

#2

Unless you dropped a valve head, the pistons should be fine. Pull the head…you will probably have to replace several (or all valves), and check the rocker shafts to see if the head is broken at a rocker shaft boss…yes it can be repaired. Chuck

#3

Thanks Chuck. Rebuilding the head - any idea on ballpark cost for that? It’s nothing you can do at a home shop is it?

#4

My advice would be throw the head in the spares pile and just purchase a used head and slap it on. Also $1150 shipped sounds like a ton of money for a used motor. I would search the boards and junkyards for a somewhat local engine and save some money.

#5

Buy a used head, $200-300, have a machine shop do a valve job, they will check the cam and head for cracks and warp…Valve job should be around $200-250…Probably 50% chance you would need a new cam. If you decide to do your old head, I can supply some used valves, otherwise they add quite a bit…I would be worried about stress from the broken belt causing problems down the road with the rockers or the head casting itself…

Al

#6

Two years ago when I bought my car I found out the head was bad. I got the following quote for the major items:

Rocker shafts (2) - $118
Rocker arms (12) - $335
Valve guides (12) - $98
Machine shop - $250
Labor to rebuild head - $1,128

There were some other minor items, such as camshaft seals and o-rings, timing belt, etc.

Total to rebuild my head was over $1,900. I bought a rebuilt head from a machine shop in St. Louis off Ebay for $450.

#7

Buy a used car.
Pull the engine and add new belt to the new used engine.

Sell car parts.
Keep car parts as spares.

That is how i came to own 17 in the past 5 years.
I’ve got e30.

RP

#8

Yes, buy any running 325i 5 speed car you can find for $500. Seriously, if you have a running parts car, that you can test the trans, do compression, leak down and oil pressure test, it will make life much easier. Spare front sheetmetal is nice also, not to mention the diff…

Start looking on Craigslist…

AL

#9

So it seems the consensus is to buy a used head. No mention of worrying about busted up piston tops? Anything i should look for on the pistons once the head comes off?

If i get a used head should i also send it to a machine shop for a valve job or is that if i am trying to re-use my old head?

#10

A rebuilt head you could use as is (obviously). A used head, unless it is from a known low mileage motor, should be rebuilt.

Before deciding what to do, pull the head and see how bad the damage is. Minor dings in the pistons aren’t a big deal, but more extensive damage might suggest a new motor.

#11

What Jim said…again. Assess the damage before jumping into anything. The prices above for parts are somewhat high, but I buy wholesale. The cost of building a new head varies greatly depending on what you need to replace. Note, cams can be blueprinted if scuffed or lobes are worn unevenly. High mileage rocker arms should be replaced because they loose their pad shape. Finally, building a DE head is very different from building a race head. For the race head, you want everything optimized…for the DE, all you really want a good street head. Good luck, Chuck