I'm still searching for the right TR. I'm curious--exactly how bad is it if you break a timing belt? Does the whole motor generally go or is it time for a valve job? Is it just a matter of buying new valves/guides, and refacing the heads? I understand that the valve will contact the pistons and bend, but are the pistons actually trashed as well? The idea of having a $100 belt break and ruin my car worries me to no end. If this happens to a flat 12 in a TR, is the motor junk? rebuildable? Too expensive to rebuild? -Jeff
The valves would be bent, for sure! I doubt that a head re-surfacing would be needed. If the RPMs are high enough, at the time the belt breaks, then I can see where a piston, or two, would also get cracked. If the rest of the car is asthetically pleasing, I can't see any reason not to re-build it. If not, then one can consider the TR as a parts car. I guess one can still sell the car, if the budget doesn't allow for a re-build.
Jeff, I have an 86 TR, rule of thumb is 5/6 yrs for the belt change. No such thing as $100 for a ferrari, unless its time to put a full tank of gas. Belts on a TR when due is probably5-8K depending on what needs to be done. There are many topics on costs on this brd you can find aot in the archives. I have yet to hear of a broken belt but it does really depend on when and where. If your at 6,ooo rpm and she snaps...yes you now have a great parts car, by another TR and keep that one for parts. I have been following this car since 84 and love my car to death, I never worry about a belt because I change them every 6 yrs...and if it does break...well then I have the best looking flower pot in the region. Don't let that stop you from buying the TR...pretty built proof, just need to find a properly serviced car with matching history and keep up to date on the service.
Under the assumption that the belt broke and you are looking at a TR with a non functional engine; my opinion is that a good deal more of the motor is trash than you anticipate. Certainly several valves will be bent, but the pistons that bent the valves will have suffered some internal (not necessarily visible) damage and are and will continue to be a grave reliability concern. I have known motors where the valves hit the pistons to harbor bent crankshafts and bent connecting rods (not Ferrari engines). Me, I would pass. The risk reward relationship is very far south.
Mitch, I don't think he is looking to buy a TR with a blown engine but is simply asking what if the belt breaks after he buys it. Buyers remorse before the purchase.
Thanks for the replies. So far the only belt failure I've heard of is someone from this forum. They had 42,000 on theirs when the belt went. Paranoia! -Jeff
I personally know someone whose had a cam belt in his TR break a little more than 5 years and 45k miles after his last cam belt service. He had a leaking cam seal and had been told by the dealer that it needed replacing for months prior to it breaking. The leaking oil had weakened the belts over time. It was on his roundtoit list that never got done. I beleive he said it cost him around $25k to have it repaired .
Changing belts every 6 or 7 may give you some peace of mind, but it's probably not necessary. I know of two 308's (a 1980, and a 1981) that still have the ORIGINAL timing belts. Let's see...that's 24 years and counting... This topic has been beaten to death, but the simple truth is, out of the thousands and thousands of Ferraris out there, you will be hard-pressed to find ONE firsthand that the belt(s) has broken on, regardless of time and mileage. So the odds are pretty well stacked in YOUR FAVOR. Follow the manual (which is probably way overkill as well) AND DRIVE IT.
Absolutely. The best way to keep everything running well is to drive it! I'm sure there have been belt snafus, but they aren't at all common - I really don't know of any first hand, and you do intend to maintain it, don't you? The TR is an awesome machine...
I have heard that most belts break at idle not at high RPMs and it would make sense because at idle there is less rotating inertia. Additionally, the belt breaking at idle has been my experience on another car. Breaking at idle would tend to minimize the valve/piston damage. Mark PS one of my neighbors had 50K+ on a 308 with original belts!
It's extremely rare to hear of a TR belt failure. Kindly like the US Gov. still looking for weapons of mass destruction? Buy the TR and enjoy it! pd
If the belt brakes, I suspect there won't be much damage to pistons. You'll know right away and the car won't run. If a valve snaps for some other reason and the head is still in there bouncing around while the engine is running, well, in that case it will indeed damage the piston.
You can have damage to a piston that is not visable unless you remove it from the engine, and have it magnafluxed or sonic checked for cracks. Many times a ring land can be crushed and you would never beable to tell with the piston still installed in the engine. If you can see were the valve hit the piston(and you most defenatly will) then depending at what rpm the engine was running..you could have more damage the you know. A conn rod could bend..the con rod bearing could get wiped out, etc,etc. Mind you like others have said the belts snapping are few and far between,but if your are going to purchase a TR be sure to get the belts changed if the service history is not complete aleast for the last 5 years. Worst case is the belt snapps at high rpm valves break and bend and get smashed into the cylinder head..then the piston gets smashed into chucks which falls into the sump and the resulting matel bits find there way in between the crank and the main bearings and the wipes out the crank. Even before this happends..with in a matter of seconds,you will need the following 2 new or used cylinder heads new set of pistons new set on con rods new crankshaft(or recondition your old one if possiable) new oil pump (because of the metal from the piston) new rings more then likely atleast 3 cylinder liners piston pins and bushings main bearings con rod bearings all gaskets possiable valve springs and retainers valve guides and seals timing belts have the cams checked for damage from the valve being rams up against it when the piston made contact with it I have seen a timing chain break on a Lambo Diablo due to a faulty tensioner. The list above is what we had to do inorder to put the engine right again. Cost over 40,000 to do this job. Please don't skimp on this service..just get it done and you'll save in the long run. Trust me. Tom
Tom - good points and appreciate your insight as a mechanic. At what point does it just become cheaper to replace the engine rather than rebuild? Just a thought. Thanks, Shan
Anecdotal evidence suggests most belt failures come from oil leaks on them. I've read a zillion threads here on belt failures and I can say that they seem to be rare, and oil leaks are almost always mentioned in the same breath. (Standard disclaimer: my car has a chain) Ken
Most cam belts aren't in danger of a breaking point at the service interval, but the cam belt tensioners are worn which in turn can result in a slipped belt or other belt failure. The belts themselves are typically very durable, way beyond the service interval. Make sure if you check service records the tensioners are replaced.