Hello on my Fiat 500 with a 650 engine. The exhaust is blowing near where it exits at the rear of the engine not very easy to get to. Is this a common problem ? I would like to try and fix it myself, is there a recommended procedure for changing what I assume is the blown gasket ? How much do I need to dismantle given the nuts are all rusty. Thank you Bryan.
Technical Exhaust leak
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Technical
Exhaust leak
Yes it is definitely the gasket between the cast iron elbow and the cylinder head behind the engine e.g. facing the front of the car. I assume I dismantle the joint between the elbow and the exhaust pipe, then the elbow from the cylinder head. I think on refixing you do up the elbow to exhaust pipe first then the cylinder head joint. Where is the best place to get a gasket ? please.
Not for us in the UK since we had that wonderful dream thing called brexit
my first call for parts is Motobambino or eBay
I totally forgot about Brexit, what a right mess that is for you guys.Not for us in the UK since we had that wonderful dream thing called brexit
my first call for parts is Motobambino or eBay
Apologies about the bum steer. Ricambio and Middle Barton Garage (can be expensive) are other ports of call OP.
the hobbler
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When you removed the bolts that secure the manifold to the head, did they come out with clean thread, or did the threads have aluminiun in them? If they did NOT come out 'clean' you will have to remove the head and investigateas to how much thread the bolts pulled out. If the threads ARE damaged, I use the "Self-tapping steel inserts" from MEMFAST. Whatever you do, do NOT drill out the manifold to take bigger bolts---there is not (normally) enough metal in the manifold/exhaust elbow to allow for this.
I agree with the hobblers advice, plus personally on reassemble I would secure the cast iron manifolds to the head firmly, before having the weight of the exhaust pulling down as you try to locate bolts into an aluminum cylinder head, if pulled down slightily due the the extra weight the bolts can be misaligned undoing all you good work.
Referring to previous comments re brexit, personally I lost 3/4 of my customer base in a flourishing new business as a direct result of something called the Exchange Rate Mechanism (look it up if you are unaware of it) so forgive me if I don't see your point of view on that, though I would agree it has been badly handled!
Referring to previous comments re brexit, personally I lost 3/4 of my customer base in a flourishing new business as a direct result of something called the Exchange Rate Mechanism (look it up if you are unaware of it) so forgive me if I don't see your point of view on that, though I would agree it has been badly handled!
The idea with this design is to do just the opposite from that. The holes in the elbows are intentionally oversized. Secure the exhaust to the elbows, tighten the exhaust brackets to the engine block, with the bolts on the wrap-around part started into the threads of the nuts and then tighten them. Finally, secure the elbows to the head. Tightening them first risks putting a sideways strain on those dodgy threads in the aluminium. I always use copper-grease on the threads in an attempt to avoid the aluminum binding on removal.
Technically, the elbows should be loosened each time the exhaust is replaced, even if there was no problem with them. But if it's the same exhaust going back on, I don't tempt fate by doing that.
I bow to your greater knowledge on this design, it is just from a engineering point of view I feel it puts more strain on the threads in aluminum whilst locating the bolts. The last Fiat 500 I worked on was in 1978 when you could buy one for £60 and all it needed was a clutch and push rod tube seals!
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"Greater knowledge"?....I don't think!
Someone's going to come along and tell me that I'm talking rubbish anyway. I am still learning at 69, trouble is I am forgetting as well, so the bucket of knowledge is overflowing and some of the good stuff gets lost with the rubbish. I used to tell my children to try and listen to everyone, then make up your own mind. Only one person to blame then!
For the first time since we had brexit inflicted upon us I made my first purchase from Italy, 500 Mania/Ital Sprint in fact. Prices are still good even after any add ons but instead of a simple delivery not I got a veritable ream of paper work, 13 A4 sheets to be exact which almost weighed more than the item I bought.
the hobbler
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You beat me David---when I did an order with "D'angelo Motori" ( and just for the record, most of their gear is good) I ONLY got 10 sheets of paperwork!For the first time since we had brexit inflicted upon us I made my first purchase from Italy, 500 Mania/Ital Sprint in fact. Prices are still good even after any add ons but instead of a simple delivery not I got a veritable ream of paper work, 13 A4 sheets to be exact which almost weighed more than the item I bought.
Regarding parts for classic cars and the varying costs from different suppliers, are you comparing like for like? If you find a good supplier selling you quality parts with a warranty for older vehicles you should support them. Places like eBay are full of companies selling spurious parts from China and India etc. which in no way meet the original specifications. These days a lot of people only buy on price, as in knowing the price of everything and the value of nothing!
As for Brexit, I agree it is being handled badly on both sides, however you lost get over it! . Some of us are old enough to have traveled and traded with Europe before the Common Market, E.U. etc. with no problem. So we know it is bureaucrats and civil servants on both sides of the channel that are deliberately causing the problems we are experiencing for their own ends!
As for Brexit, I agree it is being handled badly on both sides, however you lost get over it!
. Some of us are old enough to have traveled and traded with Europe before the Common Market, E.U. etc. with no problem. So we know it is bureaucrats and civil servants on both sides of the channel that are deliberately causing the problems we are experiencing for their own ends!Hi. I have recently refurbished the original exhaust on my classic fiat 500 and when I refitted it, I replaced the gaskets all round and copper nuts between the manifold and exhaust but retained original bolts and washers between the manifold and engine. I have found that both the nuts and bolts have worked lose (to the point that I have lost two of the original bolts from the front). There is reference self tapping steel inserts above. I have not used these before. Can these be easily fitted to the front of the engine (where access is pretty tight)? I have also seen reference elsewhere to Norlock washers and copper paste working. Is this an easier option to fit and if so is there a greater a risk that the bolts work loose compared to steel insert?
the hobbler
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Due to the 500s habit of either shedding the exhaust-manifold/cylinder-head bolts OR them coming out with bits of the cylinder-head embedded in the thread, when I worked at Radbourne racing (in my yoof) we fitted the "self-tapping steel inserts" that Abarth supplied FROM NEW when we up-rated a 500 to 652cc. This was an actual "Factory Abarth modification" (i have the paper-work to prove it). The "MEMFAST" self-tapping steel inserts are practically identical to those we fitted. They are not difficult to fit---just requires some accurate drilling, which is easier to do with the head OFF. The 126 heads do not seem to have as much metal around the cylinder-head thread holes, so I make studs and fit them TIGHTLY into the cylinder-head instead of using bolts. For those that are interested in that modification (which has never failed on me) I will be very happy to send them details of the stud dimensions and how I fit them--just e-mail me--- [email protected] Lastly, sadly fully rectifying an exhaust leak at the back of the engine (bulkhead end) is nearly always a "head-off" job.
. I'm interested in getting the stud solution and will ping mail over this weekend. Kinda regretting taking the exhaust off in the first place.
